Index: t3lib/class.t3lib_extmgm.php
===================================================================
--- t3lib/class.t3lib_extmgm.php	(revision 9835)
+++ t3lib/class.t3lib_extmgm.php	(revision )
@@ -319,7 +319,7 @@
 								}
 							}
 						} else {
-							if (strstr($str, $typeDetails['showitem']) != FALSE) {
+							if (strpos($typeDetails['showitem'], $str) != FALSE) {
 								$fieldExists = TRUE;
 							} else {
 								foreach ($GLOBALS['TCA'][$table]['palettes'] as $palette => $paletteDetails) {
@@ -331,12 +331,12 @@
 							}
 						}
 					} else {
-						if (strstr($str, $typeDetails['showitem']) != FALSE) {
+						if (strpos($typeDetails['showitem'], $str) != FALSE) {
 							$fieldExists = TRUE;
 						} else if(is_array($GLOBALS['TCA'][$table]['palettes'])) {
 							foreach ($GLOBALS['TCA'][$table]['palettes'] as $palette => $paletteDetails) {
 								if (preg_match('/\b' . $palette . '\b/', $typeDetails['showitem']) != FALSE
-								&& strstr($str, $paletteDetails['showitem']) != FALSE) {
+								&& strpos($paletteDetails['showitem'], $str) != FALSE) {
 									$fieldExists = TRUE;
 								}
 							}