Question: any chance that wireless access point, wrt54g type with ddwrt, could cause a cisco router to go buggy and drop dhcp requests and other network issues?

looking for some advice as the units are within a foot of each other and this is turning into a blame game between two companies that installed the equipment.
thanks
gd

Answer: 
Are these hooked into the same network in anyway (wrt54g goes into the same switch as the router, or the router itself)? If that is the case, maybe you have some **IP conflicts**. If they are both in the same broadcast domain, and are both running dhcp, then when clients request IP addresses you don't know which will answer. 

Since the dhcp servers won't know who is given what, you might end up with duplicate IPs.

Physically, the would not interfere with each other.
I once had a device with a flakey powersupply. I don't understand exactly why, but it caused issues with other devices plugged into the same power distribution unit. So, if they are plugged into the same circuit, it is possible you might see something there, but I don't see where the physical location of a Wireless AP would affect a non-wireless device. 

THe other issue I have seen, is if a client has a wired and wireless connection, and the connections are set to Bridge for some reason, you can get all kinds of wierd IP duplications with some hardware based DHCP servers. My case was a SonicWall Firewall that I was using as a DHCP, and every time this one consultant was is in the office, I'd start getting IP conflict errors all over the network. The issue was traced back to the consultant's laptop creating a second path in the network that messed with the processing of DHCP requests and acknowledgements.