I have a Motorola RFS4000 controller. I have wifi client randomly dropping off the WLAN and then automatically reconnecting. I've enabled a syslog server and got the error when the WiFi client drops.
mobile-unit initiated disassociation (reason code 8)
Oct 24 12:10:09 RFS4000 %CC-6-STATIONUNASSOC: Station B8-8D-12-09-AB-04 un-associated from radio 3 wlan 2 : starting tkip countermeasures (reason code 14)