windows process cases?

Hi, I have two almost identical machines running windows2000 with the same updates service packs etc

In task manager, one of them has "winlogon.exe" in all lowercase letters, the other has "WINLOGON.EXE" in all uppercase letters

Is this normal? Which is the normal capitalization for this process?

Does the all caps one indicate that process has been replaced by a trojan or something like that? If I make a checksum of each should they be identical?

Any help or advice would be appreciated

I can't wait until Windows Vista comes, though.  People are gonna go apeshit over it, because it has Windows 2003 code AND has more GOOEY features.  People are gonna fight and bitch over it just like this for AGES.