I've solved a similar problem on a different platform by creating substitution tables.  If the files are all going one way, pretty much any substitution will work ( _ for space, &c).  Where files will be going bi-directionally, it will take a little more work to come up with substitutions that will always (or mostly) work.

>>> Christian Lheureux <[log in to unmask]> 11/08/99 12:59PM >>>
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Now, I have one little problem left ... filenames ! Windows filenames allow
spaces and many other characters that Posix on MPE will not allow. Then I
have a problem when I attempt to copy from my PC to the HP3000 two files
with names differing only by a space or anything similar... Anyone got a
suggestion on how to circumvent that problem ?