I suggest you download this add in from the MS PPC support site:
<a href=http://www.microsoft.com/windowsmobile/resources/downloads/pocketpc/powertoys.mspx>Microsoft Internet Explorer Tools for Pocket PCs</a>
This PowerToy allows you to adjust Internet Explorer settings on your Pocket PC. You can enable/disable JScript support, as well as changing the amount of storage available for temporary Internet files.