iPhone 4 wont connect to airport express

I have an upstairs and downstairs Airport express. My iPhone 4 will connect to the upstairs one, but not the downstairs one. I have reconfigured the Airport and wiped out network settings on the iPhone.

The iPhone sees the network but does not accept the WPA2 passphrase that allow 2 macs and my pc to connect to the network. It simply comes back with: Unable to join the network "Downstairs"

This is what I got before a hard reset of the airport and continue to get after the hard reset. Also wiped network settings on phone, powered down and then powered up.

Same phone connects fine to wireless upstairs (same settings, DHCP) and to external wifi networks.

Any ideas on how to get connected?

Update:
Network Sniffer shows 2 networks: Downstairs and Airport (old name pre-reset) the mac addresses read
SSID Downstairs BSSID 10:9AD:84:1F:E4
SSID Airport BSSID 10:9AD:84:1F:E3

Thanks,

Jay