Index: /trunk/src/VBox/Devices/Network/slirp/libalias/alias_dns.c
===================================================================
--- /trunk/src/VBox/Devices/Network/slirp/libalias/alias_dns.c	(revision 22880)
+++ /trunk/src/VBox/Devices/Network/slirp/libalias/alias_dns.c	(revision 22881)
@@ -169,6 +169,6 @@
     struct udphdr *udp = NULL;
     union dnsmsg_header *hdr = NULL;
-    udp = (struct udphdr *)((char *)pip) + (pip->ip_hl << 2);
-    hdr = (union dnsmsg_header *)&udp[1];
+    udp = (struct udphdr *)ip_next(pip);
+    hdr = (union dnsmsg_header *)udp_next(udp);
 
     if (hdr->X.qr == 1)