SUCCESS! That is, using WorldTalk on the MobilePro 790.
I found the solution on some forum. Very simple - it's the URL you type in.
The correct URL to use to access Hotmail is -
http://mobile.msn.com/pocketpc
I was able to log in - get my email - write an email to myself - reply to an email - delete messages from my Inbox - and get my addressbook.
The calendar did not show up on this page - but I suppose is superfluous considering you are logging on with your handheld that already has your calendar on it.
However, I was not able to get this link to access my Hotmail with my Hitachi Eplate with the Internet 3.01. It said something about a secure link could not be established. I do have the 128-bit encryption plus add-in installed. I suppose this belongs now on the HPC Pro thread.