I added a bug in 2.5.23 when cleaning up something that
was broken ... it wasn't broken in quite the way I had
thought at the time!

This fixes a problem some folk have reported recently
with ISO-IN, by masking a common non-error outcome.

Please merge to Linus' tree, on top of the one patch
you already have queued.  Thanks to Nemosoft for such
quick turnaround on testing!