asp.net (html / blazer access) keyboard modes

Is there way to make a keyboard automatically go into a "numeric mode"
when the mobile app renders code for html or blazer clients? Example,
a client with a TREO 650 running the blazer browser...how can you set
the mode to numbers so when the user uses the keyboard they don't have
to hit the "blue shift" key to get numbers into the field?

I've also been playing around with the idea of making the amount field
a separate window, and on this window (for the TREO), display a numeric
key pad and let the users enter in the amount by the touch screen. Has
anyone seen and code samples or ways to do something like this?

Thanks!

Scott