The MonTel Client uses the Jet Database Engine, which is the same as the one that drives Access 97. The chances are that any issue that affects Access 97 or other Jet Engine Products will occur in MonTel in the same circumstances.
Netware handles file locks differently from Windows networks. The Jet Engine is particularly heavy on file locks, and your Server may report the error message: Station x record lock threshold exceeded. Total violations #####.
For more information see: http://support.novell.com/cgi-bin/search/searchtid.cgi?/10025712.htm
Increase the MAXIMUM RECORD LOCKS PER CONNECTION to 10000 and the MAXIMUM RECORD LOCKS to 150000 as a good starting point (you may need to make it even high in sites with more than 100 extensions).
Microsoft also have this topic (Q102522) about the "Record Lock Threshold" on Netware servers. http://support.microsoft.com/support/kb/articles/q102/5/22.asp?id=Q102522