Intermittent "cannot execute [Exec format error]" (using ksh)

Every so often, I'll be typing along at the shell and I'll get something like:


$ ls -lt | head
head: head: cannot execute \[Exec format error\]

This only happens to me on macos (not linux, not cygwin, not Solaris, ...). Apparently others have been so afflicted (see http://forums.macosxhints.com/showthread.php?t=99566) and have found a simple way to reproduce the problem:

$ touch foo; find . -name foo | while read f; do test -f bar || mv $f bar; done

This pipeline works fine under bash.

Thoughts?


Thanks,
Jeff