PRI intense debug span

Can anyone help me regarding this issue

i type “pri intense debug span 1”

but frames are not visible on asterisk CLI

i set verbose to 100 too but nothing appears

i can make successful call using my E1 cards BUT y i cant see frames

???

is there need to change some debug parameter in driver files??

I’m using one of the latest build of Asterisk (I’m taking sources from svn) and it works fine for me.
The non intense version of debug is not really working…
Asterisk is running in a safe mode in a remote environment using 21 verbose.
Rgs