How do you pass-through GRE?

Question

I understand UTM won't handle GRE. So I just want to pass it through to another server that will handle it. But I keep getting Default Drop even though I created a NAT and rule to pass GRE through. UTM is ignoring my NAT rule, IP protocol 47.

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Remuflon · Answer

Hi Bob, thanks for replying. 
 I did in fact solve my problem. Turns out I had it working long ago, probably 100 hours earlier. But because I had a "NAT hairpin" situation, I didn't see it working from within my local network. I discovered by accident that it was working perfectly from an outside IP. 
 I manually updated my iptables in UTM and built startup scripts for my tunnels and installed them into /etc/init.d/rc3.d. 
 It's all rockin' now.