WRTU54G-TM not keeping its IP address, generally being annoying

Question

I bought a Linksys WRTU54G-TM for the TMobile @Home service.  Setting it up is proving to be absurdly frustrating because the webbased interface refuses to acknowledge that I have given it an IP address.  I set the IP to 192.168.1.20, static IP, configured as a bridge, etc etc.  Every time I was able to bring up the web interface the IP address was listed as 0.0.0.0 on the main page, but the Status page showed the correct IP.
I shut off the wireless router part because we already have a wireless setup -- ironically a WRT54G Linux-based Linksys router that's been working without a hitch for 3 years.  Since the TMobile router and the main router are in wholly separate areas of the house, we're using a Zoom wireless access point so it can still remain part of the network.  The Zoom access point has been working flawlessly for around 2 years.
After a few minutes of trying to figure out **bleep** is going on, now the router is not responding to 192.168.1.20 at all.  
At this point I'm getting overly frustrated and about to chuck the thing through the nearest wall.  Why doesn't the webform keep the IP address?  Why does the router seem so keen on reverting to 192.168.24.1 when I've never set that as an IP address?  I won't even get into the fact that the router isn't letting me use the phone ports because that's a whole different can of worms.
Has anyone else had this amount of trouble with the WRTU54G-TM? Did I just get a lemon?

Answer 1

There's one the WRT54G Linux-based router that's serving as a DHCP server.  I've disabled the DHCP server on the TMobile router and told it to use a static IP address (192.168.1.20, WRT54G is at 192.168.1.1).  So far everything is working fine even though the web interface continues to deny that it has a proper IP address -- but only on the initial form; going to the Status page still lists the proper IP.  It doesn't appear to be causing any issues other than annoying me so I'm letting it fly (otherwise the router itself would be flying).
There was an issue earlier with the router forgetting about the connected phone when I was transferring a large file across the network but that hasn't reappeared.  We're getting some static a few seconds into phone conversations but I'm attributing that to a cordless phone that the soon-to-be-Mrs insisted on using.  Hopefully I'll be able to talk her into a VTech DS6121 setup, or something similar, so that won't be an issue going forward.  Wish me luck