I don't think it's possible unless you have POP3 or possibly IMAP access to your Hotmail account. And that of course costs money
At least that's as far as my endeavors went on that front, as I to invested in a hotmail account at the dawn of the interwebs. IT's not that I paid the account, but everyone knows that as my email address, so it owuld be rather inconvenient to change.
I got a free account through Bluebottle (just google it). It provides (I think) a choice of POP3 and/or IMAP access. It was pretty easy to set up on the Zaurus.
Since I only really use the Z as a web/email terminal if I'm traveling (My C-1000 is just
powerful enough to replace my laptop when traveling light is most desirable) I make do. You can of course check your hotmail through the netfont webrowser. The main reason I wanted to use the e-mail client is it's far more convenient for typing an email ahead of time and then imediately sending it once you connect (when I travel I often use dial-up which costs per minute of course). You could of course type your emails, save it as a text file, and then copy and paste into email via hotmails web inteface...but that's kind cumbersome.
I've just asked people that if they receive a message from my Bluebottle account that they make sure they cc the Bluebottle account even if they reply to my hotmail account.
But, who knows...someone might have come up with a work around since last I checked...