hey galechicago - me too!
This is my first post here, from my little appled mini.
I wanted to write EXACTLY the same as you did - airport cannot be activated, everything else works great.
Did a few reinstalls, running DELLEFI 1.1 about 10 times.
Did all of the software updates, rerunning DELLEFI again afterwards.
Got the latest BIOS, WLAN activated.
When WLAN is deactivated in BIOS, there is a message "no airport card installed".
When activated, it shows up in the system profiler, but cannot be activated anyhow.
There are some other posts about this issue, but not one of the proposed solutions worked here.
Hope someone can come up with a solution.
Thanks to everybody in this great community.