asterisk users - Aug 2013 - ooh323 and tcp timeout?

Hello!

I run asterisk 11.5.0 and I connect to some peer over ooh323.
But there is alternate path to the same peer over sip, but this not we 
can usually use.
So, if peer is not available over h323 I'd like to dial over sip.

I tried to test this:

iptables -D INPUT -s 192.168.6.0/24 -j DROP

and do Dial(OOH323/${EXTEN}@peer,,g)

but it waits forever.

Is it possible to set signalling timeout to ooh323?

Thank you!