remove CONFIG_ISDN entries from arch/Config.help - The real entry is

in drivers/isdn/Config.help

arch/alpha/Config.help

@@ -597,31 +597,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_SRM_ENV
   If you enable this option, a subdirectory called srm_environment
   will give you access to the most important SRM environment

arch/arm/Config.help

@@ -471,31 +471,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_ARCH_ARCA5K
   This selects what ARM system you wish to build the kernel for. It
   also selects to some extent the CPU type. If you are unsure what

arch/cris/Config.help

@@ -171,31 +171,6 @@ CONFIG_SOUND
   Kernel patches and supporting utilities to do that are in the pcsp
   package, available at <ftp://ftp.infradead.org/pub/pcsp/>.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_ETRAX100LX
   Support version 1 of the Etrax 100LX.
 

arch/i386/Config.help

@@ -900,31 +900,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_DEBUG_HIGHMEM
   This options enables addition error checking for high memory systems.
   Disable for production systems.

arch/ia64/Config.help

@@ -424,31 +424,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_ITANIUM
   Select your IA64 processor type.  The default is Intel Itanium.
 

arch/mips/Config.help

@@ -899,31 +899,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_GDB_CONSOLE
   If you are using GDB for remote debugging over a serial port and
   would like kernel messages to be formatted into GDB $O packets so

arch/mips64/Config.help

@@ -438,31 +438,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_BINFMT_ELF32
   This allows you to run 32-bit Linux/ELF binaries on your Ultra.
   Everybody wants this; say Y.

arch/ppc/Config.help

@@ -551,31 +551,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_PROC_HARDWARE
   Say Y here to support the /proc/hardware file, which gives you
   access to information about the machine you're running on,

arch/sparc/Config.help

@@ -1054,31 +1054,6 @@ CONFIG_MAGIC_SYSRQ
   keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
   unless you really know what this hack does.
 
-CONFIG_ISDN
-  ISDN ("Integrated Services Digital Networks", called RNIS in France)
-  is a special type of fully digital telephone service; it's mostly
-  used to connect to your Internet service provider (with SLIP or
-  PPP).  The main advantage is that the speed is higher than ordinary
-  modem/telephone connections, and that you can have voice
-  conversations while downloading stuff.  It only works if your
-  computer is equipped with an ISDN card and both you and your service
-  provider purchased an ISDN line from the phone company.  For
-  details, read <http://alumni.caltech.edu/~dank/isdn/> on the WWW.
-
-  This driver allows you to use an ISDN-card for networking
-  connections and as dialin/out device.  The isdn-tty's have a built
-  in AT-compatible modem emulator.  Network devices support autodial,
-  channel-bundling, callback and caller-authentication without having
-  a daemon running.  A reduced T.70 protocol is supported with tty's
-  suitable for German BTX.  On D-Channel, the protocols EDSS1
-  (Euro-ISDN) and 1TR6 (German style) are supported.  See
-  <file:Documentation/isdn/README> for more information.
-
-  If you want to compile the ISDN code as a module ( = code which can
-  be inserted in and removed from the running kernel whenever you
-  want), say M here and read <file:Documentation/modules.txt>.  The
-  module will be called isdn.o. If unsure, say N.
-
 CONFIG_SUN4
   Say Y here if, and only if, your machine is a Sun4. Note that
   a kernel compiled with this option will run only on Sun4.