diff --git a/ez-ipupdate.c b/ez-ipupdate.c
index ff093a9..eea7624 100644
--- a/ez-ipupdate.c
+++ b/ez-ipupdate.c
@@ -849,6 +849,27 @@ int is_dotted_quad(char *addr)
   return(1);
 }
 
+int is_ip_addr(char *addr)
+{
+#if HAVE_ARPA_INET_H
+  char dst[16];
+
+  if(inet_pton(AF_INET,addr,dst) == 1)
+  {
+    return(1);
+  }
+
+  if(inet_pton(AF_INET6,addr,dst) == 1)
+  {
+    return(1);
+  }
+
+  return(0);
+#else
+  return is_dotted_quad(addr);
+#endif
+}
+
 void parse_service(char *str)
 {
   int i;
@@ -1859,7 +1880,7 @@ int DYNDNS_check_info(void)
     chomp(host);
   }
 
-  if(address != NULL && !is_dotted_quad(address))
+  if(address != NULL && !is_ip_addr(address))
   {
     fprintf(stderr, "the IP address \"%s\" is invalid\n", address);
     return(-1);