DG834Gv5 doesn't pass through DHCP

[CraigHumphrey]

Hey People,

I've been running a separate DHCP server (on a Windows Home Server box) behind a DG834Gv3 quite happily for a few years now.
Recently I inherited a DG834Gv5 and thought I'd use to extend my coverage. But the v5 doesn't support any form of bridging/repeating, so figured I swap it out for my v3 and use the repeater mode in the v3.
Plugged it in, configured it up, found my ADSL connect speed had jumped from ~16,000/850Kb/s to ~18,000/1,000Kb/s. Nice
But now none of my wifi devices (mixture of iPhones, iPod Touches, Win7/XP laptops and a win7 desktop) could connect properly. They would connect to the wifi (strong signal) but couldn't pick up an IP address from the DHCP server.
Numerous attempts failed to get an IP.
I even tried a few different versions of the firmware (6.00.25, 1.6.00.33, 1.6.00.35 and 1.6.01.34) to no avail (though it was interesting to see various features/functionality come and go).

Pulled out Microsoft's NetMon on the DHCP server and the WinXP laptop to capture the network traffic. All good at the DHCP server end, I could see the DHCP requests and responses, but on the WinXP client I could only see the DHCP requests.
It looked like the v5 was filtering out DHCP responses going from it's ethernet ports to the WIFI.
Strange.

Has anyone else seen this?

Static IPs on the WIFI devices works fine, but isn't ideal. I even found that just occasionally (usually after some minutes) some devices would get issued an IP, but it's fairly random and with the likes of the iPod Touches attempting to get new IPs every time they're woken up...

Thanks
Craig

[CraigHumphrey]

FYI the bottom of THIS article seems to suggest that some routers may have problems passing DHCP through. Sounds like the DG834Gv5 is one of them...