some cleanup after https://bugs.eclipse.org/bugs/show_bug.cgi?id=406646
diff --git a/testplugins/org.eclipse.objectteams.otdt.tests/test.xml b/testplugins/org.eclipse.objectteams.otdt.tests/test.xml
index aa2083e..3fb5352 100644
--- a/testplugins/org.eclipse.objectteams.otdt.tests/test.xml
+++ b/testplugins/org.eclipse.objectteams.otdt.tests/test.xml
@@ -9,7 +9,7 @@
 	<!-- sets the properties eclipseTest-home, and library-file -->
 	<property name="plugin-name" value="org.eclipse.objectteams.otdt.tests"/>
 
-	<property name="library-file" value="${test.eclipseDir}/plugins/${org.eclipse.test}/library.xml"/>
+	<fail unless="library-file">Property "library-file" needs to be passed by the caller.</fail>
 
 	<!-- This target holds all initialization code that needs to be done for -->
 	<!-- all tests that are to be run. Initialization for individual tests -->