Socket programming; server side; signal 11(segmentation fault) ??!!

Hi!
I'm implementing a simple chat server.
It starts up fine, binding et.al. is fine...
then when i connect to it using telnet 127.0.0.1 19471
(this is the port number i'm listening on #define CONTROL_PORT 19471),
the server crashes.
the messege at server terminal is:

Program has been terminated receiving signal 11 (Segmentation fault)
Press the Enter key to close this terminal ...

on the client(telnet) terminal, the msg is:

telnet 127.0.0.1 19471
Trying 127.0.0.1...
Connected to 127.0.0.1.
Escape character is '^]'.
Connection closed by foreign host.

What is going wrong?

Here's a snippet of my server code:

int main()
{
      int DataTempSock, CtrlTempSock;      //these will temporarily hold the sockets numbers for every client that connects
      int ListenerSock = socket(AF_INET,SOCK_STREAM,0);
      if(ListenerSock == -1)
      {
            perror("socket()");
            return 0;
      }

      int yes = 1;
      if(setsockopt(ListenerSock,SOL_SOCKET,SO_REUSEADDR,&yes,sizeof(int)) == -1)
      {
            perror("setsockopt()");
            close(ListenerSock);
            return 0;
      }

      struct sockaddr_in LisSockAddr;

      bzero(&LisSockAddr,sizeof(struct sockaddr_in));
      LisSockAddr.sin_family  = AF_INET;
      LisSockAddr.sin_port = htons(CONTROL_PORT);
      LisSockAddr.sin_addr.s_addr = inet_addr("127.0.0.1");

      if(bind(ListenerSock, (struct sockaddr*) &LisSockAddr, sizeof(struct sockaddr_in)))
      {
            perror("bind()");
            close(ListenerSock);
            return 0;
      }

      if(listen(ListenerSock,2))
      {
            perror("listen()");
            close(ListenerSock);
            return 0;
      }

      OnlineUsersList OUL;      //this is the one and only OnlineUsersList object
      fd_set MasterFDSet,TempFDSet;      //fdsets to hold active socket lists

      //after every 5 seconds, the server will check if all connected clients are still online or not
      //this is to make the server resilient against remote system crashes etc. which diconnects remote client
      //before proper logout!
      struct timeval ServerCheckTimer;
      ServerCheckTimer.tv_sec = 5;
      ServerCheckTimer.tv_usec = 0;

      int MaxSock = ListenerSock;      //maintain maximum socket number for select() call

      char ReadBuffer[1501];      //all messeages received will be temporarily stored here
      int readlen = 0;      //number of bytes received

      FD_ZERO(&MasterFDSet);
      FD_ZERO(&TempFDSet);

      FD_SET(ListenerSock,&MasterFDSet);

      int RetValofSelectFn=0;

      while(1)
      {
            TempFDSet = MasterFDSet;
            if((RetValofSelectFn = select(MaxSock+1,&TempFDSet,NULL,NULL,&ServerCheckTimer)) == -1)
            {
                  perror("select()");
                  close(ListenerSock);
                  return 0;
            }
            else if(RetValofSelectFn)      //something's incoming, let's find out what
            {
                  for(int i=0; i<=MaxSock; i++)
                  {
                        if(FD_ISSET(i,&TempFDSet))
                        {
                              if(i == ListenerSock)      //someone new wants to connect
                              {
                                    ConnectNewClient(OUL, ListenerSock, &MaxSock, &MasterFDSet);
/*                                    int sockaddrlen = sizeof(TempSockAddr);
                                    if((TempSock = accept(ListenerSock,(struct sockaddr*)&TempSockAddr,(socklen_t*)&sockaddrlen)) == -1)
                                    {
                                          perror("accept()");
                                    }
                                    else
                                    {
                                          if(TempSock > MaxSock)      MaxSock=TempSock;
                                          FD_SET(TempSock,&MasterFDSet);
                                          printf("\nNew connection accepted from %s on socket %d\n",inet_ntoa(TempSockAddr.sin_addr),TempSock);
                                    }*/
                              }
                              else
                              {
                                    bzero(&ReadBuffer,sizeof(ReadBuffer));
                                    if((readlen = recv(i,ReadBuffer,sizeof(ReadBuffer),0)) <= 0)
                                    {
                                          if(readlen == 0)
                                          {
                                                printf("\nClient at socket %d closed connection!\n",i);
                                          }
                                          else
                                          {
                                                perror("recv()");
                                                printf("\nError reading socket %d, closing that connection\n",i);
                                          }
                                          FD_CLR(i,&MasterFDSet);
                                          close(i);
                                    }
                                    else      //recv() successful
                                    {
                                          for(int j=0; j<=MaxSock; j++)
                                          {
                                                if(FD_ISSET(j,&MasterFDSet))
                                                {
                                                      if(j != i && j != ListenerSock)
                                                      {
                                                            if(safesend(j,ReadBuffer,readlen,0) == -1)
                                                            {
                                                                  perror("send()");
                                                                  printf("Couldn't send messege to client at socket %d, closing that socket\n",j);
                                                                  FD_CLR(j,&MasterFDSet);
                                                                  close(j);
                                                            }
                                                      }
                                                }
                                          }
                                    }
                              }
                        }
                  }
            }
            else      //this will be the case when timeout occurs on call to select
                  //now check if all clients in OUL are still online
            {
            }
      }
      return 0;
}

int safesend(int SendSock,char *SendBuffer,int SendBytesCount,int SendFlag)
{
      int BytesSent = send(SendSock,SendBuffer,SendBytesCount,SendFlag);
      if(BytesSent == -1)
      {
            perror("send()");
            return -1;
      }
      else if(BytesSent < SendBytesCount)
      {
            int RemainingBytes = SendBytesCount - BytesSent;
            int temp = 0;
            while(RemainingBytes)
            {
                  temp = send(SendSock,SendBuffer+BytesSent,RemainingBytes,SendFlag);
                  if(temp == -1)
                  {
                        perror("send()");
                        return -1;
                  }
                  BytesSent += temp;
                  RemainingBytes -= temp;
            }
      }
      return BytesSent;
}

//whenever a client tries to connect, this function will be called
//this function
int ConnectNewClient(OnlineUsersList OUL, int ListenerSock, int *MaxSock, fd_set *MasterFDSet)
{
      //a sockaddr_in structure where information about a client requesting to get online
      struct sockaddr_in TempSockAddr;
      bzero(&TempSockAddr,sizeof(struct sockaddr_in));
      int sockaddrlen = sizeof(TempSockAddr);
      
      int TempSock;      //socket number allocated to the new client will be temporarily stored here
      
      if((TempSock = accept(ListenerSock,(struct sockaddr*)&TempSockAddr,(socklen_t*)&sockaddrlen)) == -1)
      {
            perror("accept()");
            return (-1);
      }
      else
      {
            if(TempSock > *MaxSock)      *MaxSock=TempSock;
            FD_SET(TempSock,MasterFDSet);
            printf("\nNew connection accepted from %s on socket %d\n",inet_ntoa(TempSockAddr.sin_addr),TempSock);
            printf("\nMaxSock = %d",*MaxSock);
            return (TempSock);
      }
}

As you can see...in function ConnectNewClient(),
the line printf("\nNew connection accepted from %s on socket %d\n",inet_ntoa(TempSockAddr.sin_addr),TempSock);
is getting executed..but not the printf() following it?! why so?

Please help!
Regards,
logicTRANCE