Configure WRT54GL to extend Time Capsule

I have set up a home network with Time Capsule as the primary router. I would like to use my WRTG54GL to connect to the network via ethernet and extend it for wireless access at the opposite end of my house. I changed the settings to disable the DHCP server, I named the network the same as the Time Capsule and duplicated security mode and password. I can connect with my laptop, but it initially connects with full internet access, but after about 10 seconds, I can see Airport searching for a network. It reconnects, but for about 45 seconds I have no internet access and then access returns and works fine. On my iPad, however, although it shows I am connected to the network, there is no signal indicator at the top of the screen, and all connectivity seems to be through 3G -- not the network. I assume there is a setting on the Linksys that needs changing, but I can't figure out what it is.