diff --git a/src/qtsingleapplication/qtlocalpeer.cpp b/src/qtsingleapplication/qtlocalpeer.cpp
index 332b0643f..a909cb22e 100644
--- a/src/qtsingleapplication/qtlocalpeer.cpp
+++ b/src/qtsingleapplication/qtlocalpeer.cpp
@@ -49,7 +49,7 @@
 typedef BOOL(WINAPI*PProcessIdToSessionId)(DWORD,DWORD*);
 static PProcessIdToSessionId pProcessIdToSessionId = 0;
 #endif
-#if defined(Q_OS_UNIX)
+#if defined(Q_OS_UNIX) || defined(Q_OS_OS2)
 #include <sys/types.h>
 #include <time.h>
 #include <unistd.h>