Index: /FCKeditor/trunk/editor/_source/internals/fck.js
===================================================================
--- /FCKeditor/trunk/editor/_source/internals/fck.js	(revision 601)
+++ /FCKeditor/trunk/editor/_source/internals/fck.js	(revision 602)
@@ -761,4 +761,14 @@
 }
 
+function _FCK_MouseEventsListener( evt )
+{
+	if ( ! evt )
+		evt = window.event ;
+	if ( evt.type == 'mousedown' )
+		FCK._MouseDownFlag = true ;
+	else if ( evt.type == 'mouseup' )
+		FCK._MouseDownFlag = false ;
+}
+
 function _FCK_EditingArea_OnLoad()
 {
@@ -768,4 +778,9 @@
 
 	FCK.InitializeBehaviors() ;
+	
+	// Listen for mousedown and mouseup events for tracking drag and drops.
+	FCK._MouseDownFlag = false ;
+	FCKTools.AddEventListener( FCK.EditorDocument, 'mousedown', _FCK_MouseEventsListener ) ;
+	FCKTools.AddEventListener( FCK.EditorDocument, 'mouseup', _FCK_MouseEventsListener ) ;
 
 	// Create the enter key handler
Index: /FCKeditor/trunk/editor/_source/internals/fck_gecko.js
===================================================================
--- /FCKeditor/trunk/editor/_source/internals/fck_gecko.js	(revision 601)
+++ /FCKeditor/trunk/editor/_source/internals/fck_gecko.js	(revision 602)
@@ -41,4 +41,6 @@
 	this._ExecDrop = function( evt )
 	{
+		if ( FCK._MouseDownFlag )
+			return ;
 		if ( FCKConfig.ForcePasteAsPlainText )
 		{
Index: /FCKeditor/trunk/editor/_source/internals/fck_ie.js
===================================================================
--- /FCKeditor/trunk/editor/_source/internals/fck_ie.js	(revision 601)
+++ /FCKeditor/trunk/editor/_source/internals/fck_ie.js	(revision 602)
@@ -98,4 +98,6 @@
 function Doc_OnDrop()
 {
+	if ( FCK._MouseDownFlag )
+		return ;
 	var evt = FCK.EditorWindow.event ;
 	if ( FCKConfig.ForcePasteAsPlainText )