With all the progress Microsoft & RIM have made with integrating Live and other services on the BlackBerry I was surprised when I came across this little tidbit. It turns out that you cannot access hosted Microsoft Office Outlook Live email on your BlackBerry.
It turns out that Microsoft is using another proprietary HTTP (Surprised?) to access the Microsoft Outlook Live software. The funny part is that if you install the Microsoft Outlook Live connector on your PC it will also cause any attempt to synchronize with Outlook to fail since it changes the MAPI profile which BlackBerry desktop manager uses to synchronize.
RIM’s solution? Use a different email account. 
Billy Not Registered
Posted: October 1, 2008 at 4:02 PM EST from my BlackBerry 9000
I can add my Windows Live Custom Domain Account (Hotmail, like Office Live Small Business) without Problems over the Browser!
It works since a few weeks…