Problem with CTHREAD methods

I have a design where a producer and a consumer are connected together through a simple packet interface. The consumer thread is just executed once. I did not understand what is wrong with it. Here is the code. The second module is executed once at the beginning of the simulation and is not executed after.

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: cmMac.h :

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#ifndef CM_MAC
#define CM_MAC

SC_MODULE(cmMac) {
   sc_in_clk     Clk;
   sc_in<bool>   Rst;
   sc_out<long>   txDout;
   sc_out<bool>  txDv;
   sc_out<bool>  txSof;
   sc_out<bool>  txEof;
   sc_out<char>  txMod;
   sc_out<bool>  txErr;

   SC_CTOR(cmMac) {
      SC_CTHREAD(cmMacSend, Clk.pos());
      //reset_signal_is(Rst, false);
      cmMacInit();
   }

   ifstream inFile;

   void cmMacInit();
   void cmMacSend();

};

#endif

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: cmDutmodel.h:

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#ifndef CM_DUTMOD
#define CM_DUTMOD
//#include "cm_mem.h"

SC_MODULE(cmDutmodel) {
   sc_in<bool>      Reset;
   sc_in_clk        Clk;
   sc_in<long>      txDin;
   sc_in<bool>      txDv;
   sc_in<bool>      txSof;
   sc_in<bool>      txEof;
   sc_in<char>      txMod;
   sc_in<bool>      txErr;

//   cmMem<sc_uint<70>,1024>  Fifo1;
   bool                  inPkt;
   sc_uint<32>           wrPtr;
   sc_uint<32>           rdPtr;
   sc_uint<1>            wEn;
   sc_uint<32>           pktSize;

   SC_CTOR(cmDutmodel) {
      SC_CTHREAD(cmDutmodelRx, Clk.pos());
      inPkt = false;
      wrPtr = 0;
      rdPtr = 0;
      //Fifo1.memAddrA(wrPtr);
      //Fifo1.memDinA(txSof,txEof,txErr,txMod,txDin);
      //Fifo1.memWenbA(wEn);
   }

   void cmDutmodelRx();
};
#endif