Cisco :: AP1252 - Authenticating Client Computers Onto Wireless Network?

I am having problems authenticating client computers onto the wireless network using a Cisco AP1252 via radius
 
Setup:

I have a Cisco AP1252 wireless Access Point connected to a Cisco ASA5510 on subnet X.X.5.Z    The access point ip address is X.X.5.101

The ASA on another port is also connected to the wired network on a different subnet X.X.0.Z
 
On the wired network are two radius servers - Ubuntus servers running freeradius which are running fine and reliably authenticate wired users for ssh connections to the ASA and importantly to the AP1252 as well (The radius servers ip addresses are X.X.0.191 and X.X.0.192)
 
Problem:

When a wireless user tries to connect to the wireless network via the AP1252 after being disconnected form it for a while (or after waking from a long sleep) they are never authenticated. They just try over and over and never obtain an IP
 
Interestingly in such a case neither Ubuntu server shows any sign of receiving an authentication request from the AP  - Both ubuntu servers are running in debug mode so they show any activity - there is none

Oddly:

If i try to authenticate a user wirelessly to the AP and leave it in the usual state of trying over and over (with no visible activity on the ubuntu servers) BUT then go to a wired machine and attempt to authenticate an ssh connection to the AP1252 using a terminal command     ssh user1@X.X.5.101   THEN as soon as I hit enter on that request (and before I enter a password for the ssh connection) THE WAITING WIRELESS USER IS IMMEDIATELY AUTHENTICATED (and the ubuntu server shows the authentication activity for the wireless user

I really do not understand this and cannot use this method to facilitate wireless user authentication 
 
What might be causing this behavior - it seems like the AP sleeping and the wired ssh request wakes it up so that it sees the pending wireless user waiting and then acts on that completing the wireless user authentication request.