diff -r 43a91b33f374 -r 48e17328c155 CMakeLists.txt
--- a/CMakeLists.txt	Sun Jan 29 11:28:41 2012 +0100
+++ b/CMakeLists.txt	Sun Jan 29 22:33:14 2012 +0100
@@ -115,8 +115,26 @@
 SET(LEMON_HAVE_LONG_LONG ${HAVE_LONG_LONG})
 
 INCLUDE(FindThreads)
-SET(LEMON_USE_PTHREAD ${CMAKE_USE_PTHREADS_INIT})
-SET(LEMON_USE_WIN32_THREADS ${CMAKE_USE_WIN32_THREADS_INIT})
+
+IF(NOT LEMON_THREADING)
+  IF(CMAKE_USE_PTHREADS_INIT)
+    SET(LEMON_THREADING "Pthread")
+  ELSEIF(CMAKE_USE_WIN32_THREADS_INIT)
+    SET(LEMON_THREADING "Win32")
+  ELSE()
+    SET(LEMON_THREADING "None")
+  ENDIF()
+ENDIF()
+
+SET( LEMON_THREADING "${LEMON_THREADING}" CACHE STRING
+  "Choose the threading library, options are: Pthread Win32 None."
+  FORCE )
+
+IF(LEMON_THREADING STREQUAL "Pthread")
+  SET(LEMON_USE_PTHREAD TRUE)
+ELSEIF(LEMON_THREADING STREQUAL "Win32")
+  SET(LEMON_USE_WIN32_THREADS TRUE)
+ENDIF()
 
 ENABLE_TESTING()