diff --git a/PhpRbac/src/PhpRbac/core/lib/nestedset/full.php b/PhpRbac/src/PhpRbac/core/lib/nestedset/full.php
index b2a2616..f2db5a8 100644
--- a/PhpRbac/src/PhpRbac/core/lib/nestedset/full.php
+++ b/PhpRbac/src/PhpRbac/core/lib/nestedset/full.php
@@ -12,13 +12,13 @@ function deleteConditional($ConditionString);
 
 
 	function childrenConditional($ConditionString);
-	function descendantsConditional($AbsoluteDepths=false,$ConditionString);
+	function descendantsConditional($ConditionString,$AbsoluteDepths=false);
 	function leavesConditional($ConditionString=null);
 	function pathConditional($ConditionString);
 
 	function depthConditional($ConditionString);
 	function parentNodeConditional($ConditionString);
-	function siblingConditional($SiblingDistance=1,$ConditionString);
+	function siblingConditional($ConditionString,$SiblingDistance=1);
 	/**/
 }
 /**
@@ -118,7 +118,7 @@ function depthConditional($ConditionString,$Rest=null)
      * @param string $Rest optional, rest of variables to fill in placeholders of condition string, one variable for each ? in condition
      * @return Array Node on success, null on failure
      */
-    function siblingConditional($SiblingDistance=1,$ConditionString,$Rest=null)
+    function siblingConditional($ConditionString,$Rest=null,$SiblingDistance=1)
     {
         $Arguments=func_get_args();
         $ConditionString=$ConditionString; //prevent warning
@@ -224,7 +224,7 @@ function deleteSubtreeConditional($ConditionString,$Rest=null)
 	 * @return Rowset including Depth field
 	 * @seealso children
      */
-    function descendantsConditional($AbsoluteDepths=false,$ConditionString,$Rest=null)
+    function descendantsConditional($ConditionString,$Rest=null,$AbsoluteDepths=false)
     {
         if (!$AbsoluteDepths)
             $DepthConcat="- (sub_tree.innerDepth )";
@@ -491,4 +491,4 @@ function editData($FieldValueArray=array(),$ConditionString=null,$Rest=null)
 
 }
 
-?>
\ No newline at end of file
+?>
diff --git a/PhpRbac/src/PhpRbac/core/lib/rbac.php b/PhpRbac/src/PhpRbac/core/lib/rbac.php
index 405c99e..2d21545 100644
--- a/PhpRbac/src/PhpRbac/core/lib/rbac.php
+++ b/PhpRbac/src/PhpRbac/core/lib/rbac.php
@@ -332,7 +332,7 @@ function children($ID)
 	 */
 	function descendants($ID)
 	{
-		$res = $this->{$this->type ()}->descendantsConditional(/* absolute depths*/false, "ID=?", $ID );
+		$res = $this->{$this->type ()}->descendantsConditional("ID=?", $ID, /* absolute depths*/false);
 		$out = array ();
 		if (is_array ( $res ))
 			foreach ( $res as $v )