Milter-greylist

I have tried to debug... See my code below :

         if ((ans = malloc(NS_MAXMSG + 1)) == NULL) {
                 mg_log(LOG_ERR, "malloc failed: %s", strerror(errno));
                 goto end;
         }
         anslen = res_nquery(&res, req, C_IN, qtype, ans, NS_MAXMSG + 1);
         mg_log(LOG_ERR, "DNSRBL: %d (%s, %d, %s, %d)\n", anslen, req, 
qtype, ans, NS_MAXMSG + 1);
         if (anslen == -1)
         {
                 goto end;
         }

	It comes from dnsrbl.c. When I use the so-obtained greylist-milter, I 
receive in the log :

Nov 13 22:55:46 rayleigh milter-greylist: DNSRBL: -1 
(248.28.217.196.dnsbl.sorbs.net, 1, \ufffdt\ufffd\ufffdt\ufffd, 65536)

that indicates an error. But on the server where runs milter-greylist, I 
can launch :
dig QUERY 248.28.217.196.dnsbl.sorbs.net
and this request works ! What is the difference between a dig request 
and the request sent by milter-greylist ?

	Configuration : i386, debian testing.

	Regards,

	JKB