Dynamic dns problem

Hello

I'd like to ask about dynamic dns update issue and Checkpoint firewall that is preventing it ... at least I suppose it's Chckpoint's fault.

We use Checkpoint R55 (SecurePlatform) to route traffic between part of vlans in our network (HSZ, DMZ).
When the traffic is going through Checkpoint firewall client machines do not register in Dns forward lookup zone, they're registering in reverse lookup zone only.
I search in logs for a traffic that is blocked but didn't find anything interesting.

For vlans that are not filtered by Checkpoint (DFZ) there is no problem.
Dns Server (Windows 2003) is also in DFZ.

Do You know if something must be set on Checkpoint to let it pass ?

Any idea appreciated.

Thanks.

Hello

I have uncheck SmartDefence -> Application Intelligence -> DNS -> UDP protocol enforcement and it works.

But doesn't it compromise security ?
Why Checkpoint treat it as an attack ?


Thanks !