Index: typo3/tree.js
===================================================================
--- typo3/tree.js	(revision 2048)
+++ typo3/tree.js	(working copy)
@@ -48,7 +48,7 @@
 		// without waiting for the response
 		if (!isExpand) {
 			obj.parentNode.getElementsByTagName('ul')[0].remove();
-			var pm = document.getElementsByClassName('pm', obj.parentNode)[0];
+			var pm = Selector.findChildElements(obj.parentNode, ['.pm'])[0]; // Getting pm object by CSS selector (because document.getElementsByClassName() doesn't seem to work on Konqueror)
 			pm.onclick = null;
 			pm.firstChild.src = pm.firstChild.src.replace('minus', 'plus');
 		} else {