diff --git a/Foundation/src/FPEnvironment.cpp b/Foundation/src/FPEnvironment.cpp
index f97060d55..4deaf3bd9 100644
--- a/Foundation/src/FPEnvironment.cpp
+++ b/Foundation/src/FPEnvironment.cpp
@@ -14,6 +14,7 @@
 
 // pull in platform identification macros needed below
 #include "Poco/Platform.h"
+#include "Poco/FPEnvironment.h"
 
 
 #if defined(POCO_NO_FPENVIRONMENT)
@@ -33,11 +34,6 @@
 #endif
 
 
-// header file must be included after platform-specific part
-// due to _XOPEN_SOURCE conflict on Tru64 (see FPEnvironment_DEC.cpp)
-#include "Poco/FPEnvironment.h"
-
-
 namespace Poco {