home network issue

I have a few computers networked. All computers have multiple OS's (W7, XP,
W2K, W98). All computers are shared and work just fine with W98, W2K, and XP
.... I used the same login name on all those OS's.

When W7 came out I got the bright idea to change the login name to something
different (figured MS is 'spying' on me with that OS so used an untraceable
name). W7 is shared fine with all other NT OS's, but W98 is not an NT OS. W7
can access W98 but W98 cannot access Win7. When trying to do so, 98 pops up
a password prompt which only asks for a password (not a username and
password as NT OS's). Thus I cannot access W7 from 98.

Any (easy) solution?
TIA