@@ -267,10 +267,23 @@
 	if (string != NULL)
 		return string;
 
 	asprintf(&string, "Initialization failed for class %s!", [class name]);
 
+	return string;
+}
+@end
+
+@implementation OFNotInSetException
+- (const char*)cString
+{
+	if (string != NULL)
+		return string;
+
+	asprintf(&string, "The requested key is not in the set of type %s!",
+	    [class name]);
+
 	return string;
 }
 @end
 
 @implementation OFOpenFileFailedException