BlackBerry Messenger, or BBM, is an instant messaging service provided for anyone who uses a BlackBerry device. When you receive a message, your device plays a default chip sound or vibrates, based on the currently selected profile. If you want incoming BBM messages to vibrate while leaving the rest of the notification settings untouched, edit your sound profiles.
Scroll to the “Sounds and Alert Profiles” icon on your BlackBerry home screen. The icon looks like a speaker. Press in on the trackpad to select it.
Select the “Change Sounds and Alerts” button at the bottom of the menu. If you are not currently using the profile that you want to change, select your desired profile from the list and then start the process over by selecting the “Sounds and Alert Profiles” icon, as you will be automatically taken back to the main screen.