@@ -250,10 +250,15 @@
 
 - (id)copy
 {
 	return [OFString stringWithCString: string];
 }
+
+- (id)mutableCopy
+{
+	return [OFMutableString stringWithCString: string];
+}
 
 - (BOOL)isEqual: (id)obj
 {
 	if (![obj isKindOf: [OFString class]])
 		return NO;