diff --git a/gfx/src/os2/nsDeviceContextSpecOS2.h b/gfx/src/os2/nsDeviceContextSpecOS2.h
index 53f58a853d7..fd9f52f472f 100644
--- a/gfx/src/os2/nsDeviceContextSpecOS2.h
+++ b/gfx/src/os2/nsDeviceContextSpecOS2.h
@@ -22,6 +22,9 @@
 #define _nsDeviceContextSpecOS2_h
 
 #include "nsIDeviceContextSpec.h"
+#define INCL_DEV
+#include <os2.h>
+#include "libprint.h"
 
 class nsDeviceContextSpecOS2 : public nsIDeviceContextSpec
 {