From David Callu, "I have added the uninstall command at the end of the first file,

and the configuration file template use by the command is the second file.
 
  The command use the cmake_install.cmake file which list all file installed by the install target.
  this issue come from the CMake FAQ"

CMakeLists.txt

@@ -371,3 +371,13 @@ IF(NOT OSG_CONFIG_HAS_BEEN_RUN_BEFORE)
 ENDIF(NOT OSG_CONFIG_HAS_BEEN_RUN_BEFORE)
 
 
+#-----------------------------------------------------------------------------
+### uninstall target
+#-----------------------------------------------------------------------------
+CONFIGURE_FILE(
+  "${CMAKE_CURRENT_SOURCE_DIR}/CMakeModules/cmake_uninstall.cmake.in"
+  "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake"
+  IMMEDIATE @ONLY)
+ADD_CUSTOM_TARGET(uninstall
+  "${CMAKE_COMMAND}" -P "${CMAKE_CURRENT_BINARY_DIR}/cmake_uninstall.cmake")
+

CMakeModules/cmake_uninstall.cmake.in

@@ -0,0 +1,22 @@
+IF(NOT EXISTS "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt")
+  MESSAGE(FATAL_ERROR "Cannot find install manifest: \"@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt\"")
+ENDIF(NOT EXISTS "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt")
+
+FILE(READ "@CMAKE_CURRENT_BINARY_DIR@/install_manifest.txt" files)
+STRING(REGEX REPLACE "\n" ";" files "${files}")
+FOREACH(file ${files})
+  MESSAGE(STATUS "Uninstalling \"${file}\"")
+  IF(EXISTS "${file}")
+    EXEC_PROGRAM(
+      "@CMAKE_COMMAND@" ARGS "-E remove \"${file}\""
+      OUTPUT_VARIABLE rm_out
+      RETURN_VALUE rm_retval
+      )
+    IF("${rm_retval}" STREQUAL 0)
+    ELSE("${rm_retval}" STREQUAL 0)
+      MESSAGE(FATAL_ERROR "Problem when removing \"${file}\"")
+    ENDIF("${rm_retval}" STREQUAL 0)
+  ELSE(EXISTS "${file}")
+    MESSAGE(STATUS "File \"${file}\" does not exist.")
+  ENDIF(EXISTS "${file}")
+ENDFOREACH(file)