Setting nameservers after res_init fails doing res_query

I have an Apache module which needs to find the "real" IP address of its host.  This became an issue after my own server went behind a firewall; the previous use of gethostbyname then returned 192.168.0.x rather than the "real" address.

I found some code that looked likely and wrote a short test program, below.

Unfortunately the results indicate that it is using the default nameservers from resolv.conf, not the nameservers loaded into _res.nsaddr_list after the call to res_init.  This was called out as an issue in the original code, but the original solution (a "dummy" call to res_query) does not work on my system.

Can someone suggest where the problem lies?

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <netinet/in.h>
#include <resolv.h>
#include <netdb.h>

#define N 4096

/* --------------------------------- */
/* CODE BEGINS                       */
/* --------------------------------- */

int main (int argc, char *argv[]) {
    u_char nsbuf[N];
    char dispbuf[N];
    ns_msg msg;
    ns_rr rr;
    int i, l;

    if (argc < 2) {
        printf ("Usage: %s <domain>\n", argv[0]);
        exit (1);
    }

/* Initialize to use the Google nameservers */
     res_init();
     _res.nscount = 2;
     _res.nsaddr_list[0].sin_family = AF_INET;
     _res.nsaddr_list[0].sin_addr.s_addr = inet_addr ("8.8.8.8");
     _res.nsaddr_list[0].sin_port = htons(53);
     _res.nsaddr_list[1].sin_family = AF_INET;
     _res.nsaddr_list[1].sin_addr.s_addr = inet_addr ("8.8.4.4");
     _res.nsaddr_list[1].sin_port = htons(53);

    printf("Domain : %s\n", argv[1]);

 /* Print the A record return or the error code */
    printf("A records : \n");
    l = res_query(argv[1], ns_c_any, ns_t_a, nsbuf, sizeof(nsbuf));
    if (l < 0) perror(argv[1]);
    ns_initparse(nsbuf, l, &msg);
    l = ns_msg_count(msg, ns_s_an);
    for (i = 0; i < l; i++)
    {
      ns_parserr(&msg, ns_s_an, i, &rr);
      ns_sprintrr(&msg, &rr, NULL, NULL, dispbuf, sizeof(dispbuf));
      printf("\t%s \n", dispbuf);
    }


    // NS RECORD
    printf("NS records : \n");
    l = res_query(argv[1], ns_c_any, ns_t_ns, nsbuf, sizeof(nsbuf));
    if (l < 0)
    {
      perror(argv[1]);
    }
    ns_initparse(nsbuf, l, &msg);
    l = ns_msg_count(msg, ns_s_an);
    for (i = 0; i < l; i++)
    {
      ns_parserr(&msg, ns_s_an, 0, &rr);
      ns_sprintrr(&msg, &rr, NULL, NULL, dispbuf, sizeof(dispbuf));
      printf("\t%s \n", dispbuf);
    }
    // ---------
    return 0;
}

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sysmgr@www:~$ ./a.out www.*******.com
Domain : www.*******.com
A records :
        www.*******.com.           6H IN A         192.168.0.209
NS records :
        www.*******.com.           6H IN NS        localhost.

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