diff --git a/Modules/Platform/OSF1.cmake b/Modules/Platform/OSF1.cmake
index 5249f6081..2ca62b1a4 100644
--- a/Modules/Platform/OSF1.cmake
+++ b/Modules/Platform/OSF1.cmake
@@ -3,7 +3,7 @@ SET(CMAKE_DL_LIBS "")
 IF(CMAKE_SYSTEM MATCHES "OSF1-1.[012]")
 ENDIF(CMAKE_SYSTEM MATCHES "OSF1-1.[012]")
 IF(CMAKE_SYSTEM MATCHES "OSF1-1.*")  
-	# OSF/1 1.3 from OSF using ELF, and derivatives, including AD2
+  # OSF/1 1.3 from OSF using ELF, and derivatives, including AD2
   SET(CMAKE_SHARED_LIBRARY_C_FLAGS "-fpic")     # -pic 
   SET(CMAKE_SHARED_LIBRARY_CXX_FLAGS "-fpic")   # -pic
 ENDIF(CMAKE_SYSTEM MATCHES "OSF1-1.*")
@@ -26,5 +26,20 @@ IF(CMAKE_SYSTEM MATCHES "OSF1-V.*")
   SET(CMAKE_SHARED_LIBRARY_RUNTIME_FLAG_SEP ":")
 ENDIF(CMAKE_SYSTEM MATCHES "OSF1-V.*")
 
-# include the gcc flags 
-INCLUDE(${CMAKE_ROOT}/Modules/Platform/gcc.cmake)
+
+IF(CMAKE_COMPILER_IS_GNUCXX)
+  # include the gcc flags 
+  INCLUDE(${CMAKE_ROOT}/Modules/Platform/gcc.cmake)
+ELSE (CMAKE_COMPILER_IS_GNUCXX)
+  # use default OSF compiler flags
+  SET (CMAKE_C_FLAGS_INIT "")
+  SET (CMAKE_C_FLAGS_DEBUG_INIT "-g")
+  SET (CMAKE_C_FLAGS_MINSIZEREL_INIT "-O2")
+  SET (CMAKE_C_FLAGS_RELEASE_INIT "-O2")
+  SET (CMAKE_C_FLAGS_RELWITHDEBINFO_INIT "-O2")
+  SET (CMAKE_CXX_FLAGS_INIT "")
+  SET (CMAKE_CXX_FLAGS_DEBUG_INIT "-g")
+  SET (CMAKE_CXX_FLAGS_MINSIZEREL_INIT "-O2")
+  SET (CMAKE_CXX_FLAGS_RELEASE_INIT "-O2")
+  SET (CMAKE_CXX_FLAGS_RELWITHDEBINFO_INIT "-O2")
+ENDIF(CMAKE_COMPILER_IS_GNUCXX)