asterisk users - Oct 2006 - Is there a way to collect dtmf digits during a call? (inband)

Hi,

Does anyone knows if I can collect DTMF digits (inband) during a bridged 
call   (E1 to E1),    ?
I see the DTMF tones on the debug file but does not activate the dialplan.

My problem is,  I need to signal from the second E1 to bridge the call 
to another E1 (a third one),  if I use the transfer capability, (dialing 
#)  it works fine with one or two calls but does not work fine with more 
than 5 calls,  (don't know what's wrong yet and why,  probably delays or
something).
So I'm thinking on implementing another way to transfer by detecting an 
inband tone and performing a transfer comand on the dial plan,

any input will be greatly appreciated