Yesterday I used the Cingular MediaNet browser on my Pearl, Go to Mail and Messaging link and then click on Mobile IM, the browser will send you straight to the download link. You can download the application from AT&T and you will get the IM Messaging application. you can log into MSN, AIM and Yahoo. It seems to work fine and it's free. I did not download it from Blackberry, downloaded it from Medianet.