If you are running the Firefox 3.0 browser, each time you receive an instant message the Conversationwindow button in the Windows taskbar flashes. In addition, and by default, each new instant message is accompanied by the following security warning:
To suppress IM security warning messages
In Firefox 3.0, in the Internet Securitydialog box, click Remember this decision, and then click Allow.
Note: This procedure only suppresses the security warning that accompanies each new instant message. Users will continue to receive all other security warnings.