On the SRP 527W, ethernet 4 is labeled as LAN/WAN, but I can't find how to configure it as a WAN port. The 'VLAN settings Add Entry' help suggests that I should be able to give a VLAN a WAN 'role':
"Role
To select the radio button WAN, you sould add the WAN port to the interfaces list first, therefore you could have the VLAN as WAN role, and do 'Edit' and 'Delete' operation in WAN Interface List."
but this does not correspond with what I see in the web interface when I add a VLAN. Adding a interface on the WAN page only allows adding ATM interfaces (ie DSL).
Firmware version is 1.01.11 (004)