diff --git a/Modules/FindThreads.cmake b/Modules/FindThreads.cmake
index 5354b4da0..623b4c46b 100644
--- a/Modules/FindThreads.cmake
+++ b/Modules/FindThreads.cmake
@@ -44,25 +44,27 @@ IF(CMAKE_SYSTEM MATCHES "Windows")
   SET(CMAKE_USE_WIN32_THREADS 1)
 ENDIF(CMAKE_SYSTEM MATCHES "Windows")
 
-IF(CMAKE_SYSTEM MATCHES "HP-UX-*")
-  SET(CMAKE_THREAD_LIBS "-lcma")
-  SET(CMAKE_USE_PTHREADS 1)
-  SET(CMAKE_HP_PTHREADS 1)
-ENDIF(CMAKE_SYSTEM MATCHES "HP-UX-*")
+IF(CMAKE_USE_PTHREADS)
+  IF(CMAKE_SYSTEM MATCHES "HP-UX-*")
+    SET(CMAKE_THREAD_LIBS "-lcma")
+    SET(CMAKE_USE_PTHREADS 1)
+    SET(CMAKE_HP_PTHREADS 1)
+  ENDIF(CMAKE_SYSTEM MATCHES "HP-UX-*")
 
-IF(CMAKE_SYSTEM MATCHES "OSF1-V*")
-  SET(CMAKE_USE_PTHREADS 0)
-  SET(CMAKE_THREAD_LIBS )
-ENDIF(CMAKE_SYSTEM MATCHES "OSF1-V*")
+  IF(CMAKE_SYSTEM MATCHES "OSF1-V*")
+    SET(CMAKE_USE_PTHREADS 0)
+    SET(CMAKE_THREAD_LIBS )
+  ENDIF(CMAKE_SYSTEM MATCHES "OSF1-V*")
 
-IF(CMAKE_SYSTEM MATCHES "FreeBSD*")
-  SET(CMAKE_USE_PTHREADS 0)
-  SET(CMAKE_THREAD_LIBS )
-ENDIF(CMAKE_SYSTEM MATCHES "FreeBSD*")
+  IF(CMAKE_SYSTEM MATCHES "FreeBSD*")
+    SET(CMAKE_USE_PTHREADS 0)
+    SET(CMAKE_THREAD_LIBS )
+  ENDIF(CMAKE_SYSTEM MATCHES "FreeBSD*")
 
-IF(CMAKE_SYSTEM MATCHES "CYGWIN_NT*")
-  SET(CMAKE_USE_PTHREADS 1)
-  SET(CMAKE_THREAD_LIBS )
-  SET(CMAKE_USE_WIN32_THREADS 0)
-ENDIF(CMAKE_SYSTEM MATCHES "CYGWIN_NT*")
+  IF(CMAKE_SYSTEM MATCHES "CYGWIN_NT*")
+    SET(CMAKE_USE_PTHREADS 1)
+    SET(CMAKE_THREAD_LIBS )
+    SET(CMAKE_USE_WIN32_THREADS 0)
+  ENDIF(CMAKE_SYSTEM MATCHES "CYGWIN_NT*")
+ENDIF(CMAKE_USE_PTHREADS)