I'm currently searching the corresponding messages in a sh log on cisco to the situation when the mac-address-table is full or overloaded. I found a lot about port-security but nothing to the simple message output (target platform = generic Catalyst switches).
As I guess a lot of you guys will know this, I found it would be faster to ask here. On Cisco 6500 Nexus, I found that a mac address overload situation is when your switch mac table can fill in fast enough regarding the quantity of incoming new mac-addr (doesn't mean it's full). I don't know if this exist on a classic Catalyst switch.