asterisk users - Sep 2003 - X100P: Can I detect/react to CLASS "you got voicemail" signals?

The subject says it all...  I have an X100P and I have (for now anyway) Bell 
Canada's Call Answer which will notify you through one of those nifty CLASS 
signals that you either do or do not have voicemail.  This is not only a 
"stuttering dialtone" but some actual signal passed so CLASS-aware
phones
can detect it and flash their message waiting indicator.

I'd like to detect this (and any other of these type of signal) in asterisk,
but am not sure how to do so.   Is it possible?

Regards,
Andrew