Zigbee Network can not be started with the Ztack 2006

Hello , I am trying to start a Zigbee net with a XBEE USB S2 and a board based on the development kit of the CC2430 which implements the zstack 20006 of Texas Instruments .
The XBEE USB S2 has been upgraded the XB24-ZB firmware version for the COORDINATOR API .
The CC2430 BOARD is supposed to be an End Device.

The only time that I got that the end device logged to the coordinator was the following one :

In the XBEE USB S2 , the ZS command has been set to 1 ( zstack Zigbee 2006 ) , and I set in the CC2430 the same channel as in the XBEE USB S2 and the value of the PAN ID ( in the CC2430 ) the same value of the OI which the XBEE USB 2 has .

(When the XBEE USB S2 is started it sends frames in which the destination PAN ID requests the OI ,so it is supposed that the end device must have that value for the PAN ID).

Now I set in the XBee USB S2 the Zs value to 0 and the parameters CH and OI change S2 and I set the value of that parameters in the CC2430 . The End Device can not be logged to the Coordinator ( It is normal because the zstacks are different ).

Now I set the Zs value to 1 and the parameters CH and OI change in the XBee USB S2 and I change that parameters in the CC2430( channel in the CC2430 = CH and the PAN ID of the CC2430 to OI ). The End Device can not be logged to the Coordinator ( THIS IS NOT NORMAL BECAUSE IT IS SUPPOSED THAT THEY HAVE THE SAME STACKS ).
I try in the End Device with different values of the PAN ID and I have the same problem

Why the End Device can not be logget to the coordinator ?

Thanks.
Gorka