diff --git a/winsup/w32api/ChangeLog b/winsup/w32api/ChangeLog
index e3cadccab..533d91b6b 100644
--- a/winsup/w32api/ChangeLog
+++ b/winsup/w32api/ChangeLog
@@ -1,3 +1,7 @@
+2006-03-05  Chris Wilson  <chris+mingw@qwirx.com>
+
+	* include/sddl.h: New file.
+
 2006-02-21  Danny Smith  <dannysmith@users.sourceforge.net>
 
 	* include/ddk/ntifs,h (FILE_ID_FULL_DIRECTORY_INFORMATION): Revert
diff --git a/winsup/w32api/include/sddl.h b/winsup/w32api/include/sddl.h
new file mode 100755
index 000000000..66590b8e6
--- /dev/null
+++ b/winsup/w32api/include/sddl.h
@@ -0,0 +1,30 @@
+#ifndef _SDDL_H
+#define _SDDL_H
+#if __GNUC__ >= 3
+#pragma GCC system_header
+#endif
+
+#ifndef WINADVAPI
+#define WINADVAPI
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#if (WINVER >= 0x0500)
+WINADVAPI BOOL WINAPI ConvertSidToStringSidA(PSID Sid, LPSTR* StringSid);
+WINADVAPI BOOL WINAPI ConvertSidToStringSidW(PSID Sid, LPWSTR* StringSid);
+#endif
+
+#ifdef UNICODE
+#define ConvertSidToStringSid ConvertSidToStringSidW
+#else
+#define ConvertSidToStringSid ConvertSidToStringSidA
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _SDDL_H */