Mine was working last week!!! Its just decided to stop! 
Hi Fishbone -- have you checked the settings? There is an option to turn it off (check that it's on VIS. SIGNAL or VIS.+ACCOUST)
This is from the manual:
SIGNAL SETTINGS
You can set notification modes for the
Blue&Meâ„¢ SMS message reader. There
are three possibilities:
â’ VIS.+ACOUST.:
Blue&Meâ„¢signals the receipt of
a new message both on the control
panel display and by an acoustic signal.
Blue&Meâ„¢ will also offer to read the
message.
â’ VIS. SIGNAL:
Blue&Meâ„¢ only visually communicates
the receipt of a new SMS message
on the control panel display. The message
received can be read later (see
READ LAST MESSAGE RECEIVED and
INBOX paragraphs).
â’ READER OFF:
Blue&Meâ„¢deactivates the SMS
Message Reader so that the receipt
of a new SMS message will not be indicated
at all, and will not be forwarded
to the message system on receipt.
