--- simgear-2016.2.1.orig/simgear/scene/tsync/terrasync.cxx
+++ simgear-2016.2.1/simgear/scene/tsync/terrasync.cxx
@@ -61,7 +61,9 @@
 #include <simgear/io/HTTPClient.hxx>
 #include <simgear/io/SVNRepository.hxx>
 #include <simgear/io/HTTPRepository.hxx>
-#include <simgear/io/DNSClient.hxx>
+#ifdef ENABLE_DNS
+#   include <simgear/io/DNSClient.hxx>
+#endif
 #include <simgear/structure/exception.hxx>
 #include <simgear/math/sg_random.h>
 
@@ -509,7 +511,10 @@
     initCompletedTilesPersistentCache();
 
     if (_httpServer == "automatic" ) {
-
+#ifndef ENABLE_DNS
+        SG_LOG(SG_TERRASYNC, SG_ALERT, "ERROR: automatic terrasync http-server requested, but no DNS resolver.");
+        _httpServer = "";
+#else
         //TODO: make DN and service settable from properties
         DNS::NAPTRRequest * naptrRequest = new DNS::NAPTRRequest("terrasync.flightgear.org");
         naptrRequest->qservice = "ws20";
@@ -565,6 +570,7 @@
 
           SG_LOG(SG_TERRASYNC,SG_INFO, "picking entry # " << idx << ", server is " << _httpServer );
         }
+#endif
     }
     if( _httpServer.empty() ) { // don't resolve SVN server is HTTP server is set
         if ( _svn_server.empty()) {