The custom sounds are via Messenger Plus! this is an add on for MSN Messenger, if you send any sounds via Plus! to a mobile contact, they will not hear/see anything. This is due to the fact that As Vilkku posted, and it probably won't be done, due to the fact that mp3 sounds can not be heard by all models of mobile phones. Sorry, but do continue enjoying Plus! with your online ccontacts, and if you have any more concerns, please post back.
Enjoy the forums!
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