Hi akosnitzky,
Yes, as JSanders mentioned, one of our new features in v2.2 allows you to set a different header background color for all your different email accounts that you receive email on for the BlackBerry - not sure if that is exactly what you wanted but it is useful for distinguishing different email accounts
Anyway, some quick trial OTA links if you wanted to give the app. a spin:
For OS v4.2 (8100's, 8300's and 8800's have this by default):
http://www.blackberrysmart.com/trial.../SmartView.jad
For other OS devices:
http://www.blackberrysmart.com/trial.../SmartView.jad
Cheers,
eZainny.