[mythtv] Verbose OSD messages and DVB Signal strength

[Paul]

I'm trying to view OSD messages in the mythbackend log, specifically the 
signal strength popup which appears at the begining of the watch TV or 
channel change

the backend log indicates its set:
2007-06-11 10:08:56.181 Enabled verbose msgs: important osd

but I don't see any output!

Is there another way to get the signal strength value ? as I'm trying to 
diagnose some problems with my DVB signal

Thanks
Paul