Socket fails: Address family not supported by protocol family

Question

I'm trying to create a BSD socket with RTEMS 5 in order to implement an UDP communication. I have the following function:

   #include <sys/socket.h>

   void Network_Initialization(void)
   {
     int fd;

     fd = socket(AF_INET, SOCK_DGRAM, 0);
     if(fd < 0 )
     {
       locked_printf("Cannot create a socket: %s \n", strerror(errno));
     }
   }

During execution the following error is returned:

Address family not supported by protocol family (106)

This code corresponds with EAFNOSUPPORT. I found this error for another funtions like bind(), but not for socket(). I supposed that is something related wiht RTEMS configuration... but what?

Thanks in advance