Bumping up a very old thread because I also have the same question. I'm looking to receive an email alert whenever an AP loses network connectivity. I'm currently using a 3400 controller. I was told when it was installed that there is no way to alert from within the controller, but it may be possible via a syslog server.
The only other way I can think of to accomplish this is to add the individual ip addresses of our AP's to our monitoring software (whats up gold). But I rather not.
Thanks in advance.