Chris,
One way is to set up dial peers in your H.323 gateway router to match 911 and 9911 explicitly. You will have to prefix a 9 for the '911' match since the first 9 is stripped. Here's what I have used in the past:
dial-peer voice 91101 pots
preference 1
destination-pattern 911
port 1/0/0
prefix 911
The way I understand urgent priority is that normally CM waits for all digits to be dialed before matching a route pattern. With urgent priority enabled, once the pattern is matched, the call is sent on to the gateway, without it waiting for the inter-digit timer to expire.
The H.323 gateway matches peers by picking the first pattern matched. There seems to be no particular order in which overlapping patterns are matched - I have heard many theories on how the gateway matches and in what order. In any case, it is a different process than the Call Manager.
Hope this helps...
