[ns] error: fault segmentation

[Gisane Michelon]

I am trying add new routing protocol, but occurs the following error:
fault segmentation.
I put print in my agent.cc and see that the error occurs this part:
int myAgent::command(int argc, const char*const* argv){
Tcl& tcl = Tcl::instance();
  if (argc == 3)
 { Packet* pkt = allocpkt();
    hdr_ip* hdrip = hdr_ip::access(pkt);
    hdr_tar5* hdr = hdr_tar5::access(pkt);
          if (strcmp(argv[1],"addr") == 0 ) {
        hdr->ret = 0;
        myaddr = Address::instance().str2addr(
argv[2]);
        hdr->ret = 0;
        hdr->TTL=0;
       send(pkt,0);
        Packet::free(pkt);
        return (TCL_OK);
     }
}
Thanks,