Some ideas:

The username and/or password wasn't correct.  Try doing a "load dsmc sel 
sys:\adsm\dsm.opt" to selectively backup one file, and enter your Novell 
username and password.  Then watch to see if it actually backups the file or 
fails.  

Check your ADSM install directory on the Novell client to see if there is a 
.pwd file.  This is where the encrypted  password is kept.  Maybe for some 
reason it can't write to this directory.

You could also try putting the "NWUser servername\user:password" line in your 
dsm.opt file to get around the password file.

        Good luck
        -andy