Problem with blocked UDP packets

Hi,
I'm developing a game using the GNE Game Network Engine, and am having some 
difficulty with my firewall (configured with guarddog 2.2.0) blocking UDP 
packets I'm trying to send.  Here's the scoop;

I was using port 1234, so had specified a user protocol to open this for TCP, 
and for UDP (might be nice to be able to do both protocols in one 
definition).  Then I enabled this for my lan zone.  TCP packets went through 
fine, but the UDP packets did not.  With the firewall off completely these 
packets arrive as expected.  

So, hypothesizing that guarddog didn't like something in my setup (and having 
tried both bidirectional and not) I decided to try another port, one in the 
built in settings.  The direct play gaming looked good, so I chose port 2302, 
as it was in the desired range.  Unfortunately this yielded the same result,  
my UDP packets were dropped.  

So perhaps GNE is sending UDP on a different port, but I doubt it.  It would 
be nice if the logs showed the port as well (or do I just not see it?).  Does 
anyone have any ideas what could be wrong??

Bjorn

ps. I'm not subscribed to the list, so please make sure replies go to me as 
well :P