On Windows based mobile devices (PDA/Smartphones etc.), an alternative browser is NetFront (post back if you can't find it on google) . Think its commercial, but there was a demo last time I looked.
It handles some sites a lot better, and allows Java Virtual Machine to be used.
To bring this answer back on topic, with Pocket Internet Explorer, I am unable to sign into Excite's web mail facility, with NetFront, I am....