Can't access internet when enable filtering bridge on DMZ bridge with WAN

[xenta]

My testing PC can access internet on the OPT1 [DMZ] when disable Filtering bridge but Can't when enable.
(DMZ bridge with WAN)

There is the rule placed on the DMZ :

Proto  Source        Port  Destination  Port  Gateway
  *        DMZ net        *          ! LAN net        *            *

Does this rule was wrong ?
Or am I forget something ?

[xenta]

I find by myself !

I have make an Alias of my WAN network (WANnet) and put this rule on the DMZ :

Proto    Source        Port    Destination    Port    Gateway
  *        WANnet        *          ! LAN net        *            *