RADIUS Problems

I am having a pretty big problem that you all should be able to fix fairly quickly, but I can't seem to figure out how. I am using 2 Cisco Aironet 1130AG's with a freeRADIUS server I have all the users in it and setup, but I seem to get this error every 30seconds on the Access Points. Jun 5 08:32:49.650 S Warning RADIUS server ***.***.***.***:1812,1813 has returned. Jun 5 08:32:49.650 S Warning RADIUS server ***.***.***.***:1812,1813 is not responding. I have removed the IP addresses for obvious reasons, but could anyone tell me what this means and how to fix it?