Be careful if you are using Windows Mobile's Windows Live Messenger Mobile

[From Tien] Arne Hess at The Unwired gives a warning if your a Win Mob Treo user and your using Windows Live Messenger. His warning make a back up! "So my advice is the following: If you want to be sure, something like this will never happens to you - better don't use Windows Live Mobile Messenger on your smartphone! If you continue to use it anyway (don't say I haven't warned you) please make sure you regularly backup your buddy list on your PC:

Open Windows Live Messenger
Click Menu -> Contacts
Select "Save instant messaging contacts..."
Save the list of your contacts anywhere you will find it later again (and sooner or later - I'm sure you will need this backup as well)
And don't forget to make a backup regularly, at least once a month (or every time you've added a new contact to your buddy list)."
The UnWired