Index: src/OFMutableString.m
==================================================================
--- src/OFMutableString.m
+++ src/OFMutableString.m
@@ -17,10 +17,12 @@
 #include "config.h"
 
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
+
+#include <sys/types.h>
 
 #import "OFString.h"
 #import "OFMutableString_UTF8.h"
 #import "OFAutoreleasePool.h"
 

Index: src/OFString_UTF8.m
==================================================================
--- src/OFString_UTF8.m
+++ src/OFString_UTF8.m
@@ -18,10 +18,12 @@
 
 #include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>
+
+#include <sys/types.h>
 
 #import "OFString_UTF8.h"
 #import "OFMutableString_UTF8.h"
 #import "OFArray.h"
 #import "OFAutoreleasePool.h"