EP not receiving message from AP links fine

Hi,

      I'm working on a little AP EP communication on a pair of CC430s.   Joining and linking both seem to work fine, but when I try to send a message to the EP it's rxCallback function specified in the SMPL_Init(sRxCallback); never gets called.

In the AP I'm doing this to send a message:

          while (1)
          {
            if (SMPL_SUCCESS == (result = SMPL_LinkListen(&sLID[sNumCurrentPeers])))
            {
              led_one_on();
              //send a message back to your EP with new link information
              while(1){
                  if(SMPL_SUCCESS == SMPL_SendOpt(sLID[sNumCurrentPeers], (unsigned char *) &privateToken, 4, SMPL_TXOPTION_ACKREQ)){
                  //(rc=SMPL_SendOpt(sLinkID1, (uint8_t *)&msg[msgindex], MAX_APP_PAYLOAD, SMPL_TXOPTION_ACKREQ)))
                  break;
                  }
              }
              break;
            }

The SendOpt returns fine but the RX callback in EP is never called.   Am I missing something?  My understanding was after link is formed that AP can send a message to EP and EP rxCallback will be called and then I can do a receive to get the actual message.  Any ideas?

Thanks for the help!