Some Apple Devices not able to ping equipment in the Data-Centre devices

Hi All

We have run into a strange problem on one of our client's networks.

They are running on Cisco network infrastructure.

Summarized Network Layout:

<CLIENT SITE> various switches > CORE SWITCH > 

SSE 100 Line

<DATA-CENTRE> CORE SWITCH > CISCO ASA FIREWALL > Internet

The issue started with the client's only 2 MAC OSX machines that lost internet connectivity when connected via the WiFi adapters. Patching in using the Ethernet adapters resolved the issue. Also changing the mac addresses on the WiFi adaptors resolved the issues.

Shortly after the same issue started on the Apple Mobile devices (iPADS, iPhones etc)


Summary:

The devices are all Apple devices.
Spoofing the mac address on an effected OSX device resolves the problem.
Spoofing the mac address on an effected iOS device has not been tested as the device needs to be jailbroken to do this.
The devices connect to the Wi-Fi successfully.
Connecting the devices via a different (NetGear) wireless access point does not make a difference.
The devices gets assigned with a DHCP IP.
The device DOES register on the ARP Table on the FireWall in the DataCentre
The devices are not able to ping the equipment that is in the DataCentre.
The devices are able to ping any device that is within the client's site.
The problem is not resolved by assigning a different IP to the device.


Any advice/assistance will be greatly appreciated.