fix several small spelling errors.

src/BTrees/SetOpTemplate.c

@@ -206,7 +206,7 @@ set_operation(PyObject *s1, PyObject *s2,
 The following ifdef works around a template/type problem
 
 Weights are passed as integers. In particular, the weight passed by
-difference is one.  This works find in the int value and float value
+difference is one.  This works fine in the int value and float value
 cases but makes no sense in the object value case.  In the object
 value case, we don't do merging, so we don't use the weights, so it
 doesn't matter what they are. 

src/ZODB/Connection.py

@@ -787,8 +787,8 @@ class Connection(ExportImport, object):
         return self._reader.getState(p)
 
     def setstate(self, obj):
-        """Turns the ghost 'obj' into a real object by loading it's from the
-        database."""
+        """Turns the ghost 'obj' into a real object by loading its state from
+        the database."""
         oid = obj._p_oid
 
         if self._opened is None:
@@ -822,7 +822,8 @@ class Connection(ExportImport, object):
         # 3. Raise ConflictError.
 
         # Does anything actually use _p_independent()?  It would simplify
-        # the code if we could drop support for it.
+        # the code if we could drop support for it.  
+        # (BTrees.Length does.)
 
         # There is a harmless data race with self._invalidated.  A
         # dict update could go on in another thread, but we don't care

src/ZODB/FileStorage/FileStorage.py

@@ -530,7 +530,7 @@ class FileStorage(BaseStorage.BaseStorage,
                 return data, h.tid
             else:
                 # Get the data from the backpointer, but tid from
-                # currnt txn.
+                # current txn.
                 data = self._loadBack_impl(oid, h.back)[0]
                 return data, h.tid
         finally:

src/ZODB/cross-database-references.txt

@@ -21,7 +21,7 @@ And create a persistent object in the first database:
     >>> tm.commit()
 
 First, we get a connection to the second database.  We get the second
-connection using the first connection's `get_connextion` method.  This
+connection using the first connection's `get_connection` method.  This
 is important.  When using multiple databases, we need to make sure we
 use a consistent set of connections so that the objects in the
 connection caches are connected in a consistent manner.
@@ -71,7 +71,7 @@ Databases for new objects
 
 Objects are normally added to a database by making them reachable from
 an object already in the database.  This is unambiguous when there is
-only one database.  With modultiple databases, it is not so clear what
+only one database.  With multiple databases, it is not so clear what
 happens.  Consider:
 
     >>> p4 = MyClass()

src/ZODB/serialize.py

@@ -106,11 +106,11 @@ oid
 
     'n'
         Multi-database simple object reference.  The arguments consist
-        of a databaase name, and an object id.
+        of a database name, and an object id.
 
     'm'
         Multi-database persistent object reference.  The arguments consist
-        of a databaase name, an object id, and class meta data.
+        of a database name, an object id, and class meta data.
 
 The following legacy format is also supported.
     

src/ZODB/tests/testcrossdatabasereferences.py

@@ -29,8 +29,8 @@ class MyClass_w_getnewargs(persistent.Persistent):
 def test_must_use_consistent_connections():
     """
 
-It's important to use consistent connections.  References to to
-separate connections to the ssme database or multi-database won't
+It's important to use consistent connections.  References to
+separate connections to the same database or multi-database won't
 work.
 
 For example, it's tempting to open a second database using the

src/persistent/cPersistence.c

@@ -85,7 +85,7 @@ unghostify(cPersistentObject *self)
     if (self->state < 0 && self->jar) {
         PyObject *r;
 
-        /* Is it ever possibly to not have a cache? */
+        /* Is it ever possible to not have a cache? */
         if (self->cache) {
             /* Create a node in the ring for this unghostified object. */
             self->cache->non_ghost_count++;