A version would help. When you are asked for your username it should give you the version. I know the latest versions of Novel Netware have the version in the name bar of the main login screen. Something like:
Novel 4.0.18 SP4
If they didn't change the default passwords then you can get in easy. Otherwise SOL. BTW you are an admin at this place...right?
Another way is to go around looking at every floppy,cd, thumbdrve(little use device) anything that might have something stored on it giving usernaes and/or passwords. If it's encrypted, I'd put extra effort to decrypt it. Really other than default passwords there is no way to crack novel except I've read there was one version that you could use a printer cable hooked up to the machine to bypass it. I haven't done this and I only found it for an older version, in the threes, that it worked for. Hope this helped.
Don't you hate it when you lose your admin passwords?
BTW shouldn't this be in a different place, like windows security or *nix security?