An interesting coincidence it is that Mozillazine has posted a link to a write-up on how to access Hotmail in Mozilla Mail in its article entitled "Accessing Your Hotmail Account Using Mozilla Mail" - see my previous entry.
Read the comments (or rather, "talkbacks"). I wasn't aware of MrPostman. Judging from the comments so far, though, Hotmail Popper seems to be the best-received thus far. Keeping an eye on the talkbacks for an even better solution!