What about this:
Set up commands that you could send from your phone to your MSN name (you send it to that "big long number")
1.One command you send asks messenger to give a list of people currently online (or away or whichever statuses you wish to check with that command) from a list you have previously choosen. The list can either be the front part of their emails (the part before the @) or their current names. (You wouldnt be able to select a lot of people because of a limit on the # of characters in a text). You could also set custom names for these contacts to make the list shorter: ie: Kasey -> Kas
2.Another command can give you a list of people who have currently sent you a message (maybe do a check to see if they have been sent within the last certain number of minutes). (And a 3rd command) And then be able to ask to see the messages from a certain contact (having the name trucicated and only the messages received to be sent, no auto message you might send back).
Yes, this might take up a lot of text messages/ SMS for your plan but it is better than having one sent to your phone every time someone says something or logs in.
If what I am saying isnt clear, sorry
its been a long day
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