If it's possible, install the Linksys configuration program for the WAP11. If you are able to pull up the help file, it will specifically say AP client mode will only talk to another WAP11 (in broken english). So, at least with the WAP11, it seems it is meant to only talk to another WAP11.

I only have experience with SMC and Linksys stand-alone access points. My experience is that the WAP11 will only be a client to another WAP11. I am also aware that the guts of the WAP11 are used in many other brands. So, it is probable that other brands firmware could open up this ability for the WAP11? I don't know. I am far from a wireless expert. I'm just offering my experience.