Rocket IO Transceiver : Loss of Sync Signal Always high

Hi, I am trying to simulate a receiver using the Xilinx Virtex 2 Pro Rocket IO transceiver, but after the reset, the LOSS_OF_SYNC signal goes high and stays there. I use the 8b/10b decoding but even after detecting a K character, the transceiver does not get byte synchronized with the incoming serial stream. Is there any other logic I will need to achieve the sync ? Does anyone have any examples ? Thanks in advance for any help. Cheers, Adarsh