diff --git a/classes/Endpoint.php b/classes/Endpoint.php
index aa2cff11d32b20cd0c778694cd79118df3bb0f65..16a7fbe2b99b4ae281b90088bb2aa568ff5547f3 100644
--- a/classes/Endpoint.php
+++ b/classes/Endpoint.php
@@ -45,6 +45,10 @@ class Endpoint{
         if(preg_match("/construct/i", $q)){
           return $aux;
         }
+        if(preg_match("/ask/i", $q)){
+          $r = json_decode($aux, true);
+          return $r;
+        }
   }
   
   public function queryPost($q){
diff --git a/classes/Queries.php b/classes/Queries.php
index 3e2451ef27cd2afbd6355fd179ccf254ebbd007e..9e650c72b22a54feb3f82fe0c4360a460ae14e51 100644
--- a/classes/Queries.php
+++ b/classes/Queries.php
@@ -2,16 +2,25 @@
 
 class Queries{
   public static function uriExist($uri, $e){
-  	$q = "SELECT * WHERE{
-  	{<$uri> ?p1 ?o1}
-  	UNION
-  	{?s1 <$uri> ?o2}
-  	UNION
-  	{?s2 ?p2 <$uri>}
-  	}LIMIT 1";
-  	
-  	$r = $e->query($q);
-  	if(sizeof($r['results']['bindings'])>0){
+  	$q = "ASK WHERE{
+  	{
+  	GRAPH ?g{
+    	{<$uri> ?p1 []}
+    	UNION
+    	{[] <$uri> []}
+    	UNION
+    	{[] ?p2 <$uri>}
+    	}
+    	}UNION{
+    	    	{<$uri> ?p1 []}
+    	UNION
+    	{[] <$uri> []}
+    	UNION
+    	{[] ?p2 <$uri>}
+    	}
+    }";
+  	$r = $e->query($q); 
+  	if($r['boolean'] && strtolower($r['boolean']) !== false){
   	  return true;
   	}
   	return false;
diff --git a/classes/Utils.php b/classes/Utils.php
index 8175d512178944b244c7ee558e927506e9dbf20b..871998d86ee6204795ef1cf0c2c28304d33485ec 100644
--- a/classes/Utils.php
+++ b/classes/Utils.php
@@ -12,7 +12,7 @@ class Utils{
   
   public static function send404($uri){
   	header("HTTP/1.0 404 Not Found");
-  	echo "LODSPeaKr could not find ".$uri." or information about it.\n\n";
+  	echo "LODSPeaKr could not find ".$uri." or information about it.\nNo URIs in the triple store, or services configured with that URI\n";
   	exit(0);
   }