[shaggylive]

have you checked the "power mode" options under "wireless LAN" settings. default is typically "best battery" combined with poor antenna and i think we may have found your problem.

edit* just to let you know, i've got insurance so I set mine to "best performance", but this does generate a lot of heat and kills the battery.
edit2* what's the manufacture date on the phone? htc should honor the 1yr manufactures warranty