@Chrissy: For the text messages service, it doesn't matter what phone you have, as long as it can send and recieve text messages (which all phones can these days).
It only depends on your country and network you use.
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YourNeibour, more info should be available here, including the shorttext number:
http://go.microsoft.com/fwlink/?LinkId=193130 or
http://sms.live.com/
Depending on which page you exactly are redirected at, you might need to press on the '
learn more' links, and/or digg a bit deeper into the pages though.
More links which might contain the info:
http://home.mobile.live.com/SmsServiceSetting.mvc/ShowTou
http://home.mobile.live.com/Home.mvc/ShowSMSUsage...viceName=Messenger
Also note that I say "should", because apparently the shorttext number is hard to find sometimes.
PS: Remember that you need to set up (or check if it is still correct) the service on the mobile.live.com pages first though.
If all things fail and you can't find the number, you can remove your current phone data (on http://home.mobile.live.com/SmsServiceSetting/ShowSmsServiceSetting and don't forget the Set up Alerts preferences link on that same page) and the services you signed up for and then set it all again. You will then recieve the SMS again with more info (and thus the number in question).
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An alternative (but it might cost more) is that you actually use Messenger on your phone. Since you have a Blackberry 8800 (=fully compatible with Windows Live) and you're in Canada:
http://www.windowsliveformobile.com/en-ca/blackberry/default.aspx
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