Does anyone know what causes a folder browse delay of around 30 seconds, when browsing for folders on a Novell Netware 6.5 SP7 server?

The client os is Windows XP SP2 with latest windows updates.
The netware client is 4.91SP4 (no patches).

SLP is configured correctly and functional with SLPDA.
Automatic search for network folders and printers is turned off