One of my test routers (DLink DI-624, with no clients) has recently stopped showing up in airodump and kismet. Instead of the random ESSID that used to show, it only shows "<length: 12>." The strange thing is that I have run several WEP breaks on this particular device without any issues. Even with SSID Broadcast disabled, airodump & kismet were both usually able to discover (or decloak) in a matter of seconds. I have let airodump run for hours with no results. The PWR is well above 30-35 range.
I am curious how I can get around this, but even more importantly... I am wondering what setting in the router could really keep this device "invisible" from BT. Additionally, BT is the only one that seems to have any problems. I have an iPaq with WiFiFoFum plus all of my Windows machines see this device without any problem.