Variable Length Encrypted Passwords

[John F. Haugh II]

Real simple question -

If your company (or vendor) is presently providing a facility
to support arbitrary length passwords (where "arbitrary" is
defined to be more than 8 and less than some large number,
say 100), how do they represent passwords of 9+ characters in
length when they are encrypted in the password file?

The problem that I've encountered in the past is that an old
style password of 9+ characters will encrypt to the expected
13 character string on an old style system.  This leaves a
problem of distinguishing old 9+ character passwords from new
9+ character passwords on a new style system.

I'd prefer implemented solutions, rather than suggestions.
Suggestions I've got, what I want is compatibility.
-- 
John F. Haugh II                             UUCP: ...!cs.utexas.edu!rpp386!jfh
Ma Bell: (512) 832-8832                           Domain: jfh at rpp386.cactus.org
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