Index: t3lib/class.t3lib_tcemain.php
===================================================================
--- t3lib/class.t3lib_tcemain.php	(revision 3851)
+++ t3lib/class.t3lib_tcemain.php	(working copy)
@@ -695,12 +695,12 @@
 								if ($OK)	{
 									$sortRow = $TCA[$table]['ctrl']['sortby'];
 									if ($pid_value>=0)	{	// Points to a page on which to insert the element, possibly in the top of the page
-										if ($sortRow)	{	// If this table is sorted we better find the top sorting number
+										if ($sortRow && !$incomingFieldArray[$sortRow])	{	// If this table is sorted we better find the top sorting number
 											$fieldArray[$sortRow] = $this->getSortNumber($table,0,$pid_value);
 										}
 										$fieldArray['pid'] = $pid_value;	// The numerical pid is inserted in the data array
 									} else {	// points to another record before ifself
-										if ($sortRow)	{	// If this table is sorted we better find the top sorting number
+										if ($sortRow && !$incomingFieldArray[$sortRow])	{	// If this table is sorted we better find the top sorting number
 											$tempArray=$this->getSortNumber($table,0,$pid_value);	// Because $pid_value is < 0, getSortNumber returns an array
 											$fieldArray['pid'] = $tempArray['pid'];
 											$fieldArray[$sortRow] = $tempArray['sortNumber'];