CC2530: The end device starts behaving awkward when xdata stack size in increased to 0x400

Hi,

When i apply the fix 2.3 from http://processors.wiki.ti.com/index.php/Zigbee_Known_Issues_and_Proposed_Fixes

the end device suddenly starts misbehaving(set the application task event repeatedly which is supposed to be set only once on timer expiry) .

We need to apply the fix because the end device freezes after few days of operation.

With out the fix the device works normally.

What may be causing this instability?