Thanks for all your help. A friend with a keen interest in this problem looked at the Dell support forums where apparently there is lots of help.
The problem stems from the TrueMobile driver not working well with Pocket Microsoft 2003 (power management conflict I think). He uninstalled the TrueMobile driver and installed one from Orinoco (
www.orinocowireless.com). Now I can happily surf the net with my Axim - no thanks to Dells technical support, especially those in India.
It appears that Dell is aware of the problem, and a download will appear (eventually) in the Axim download site.
Hope this helps