allow absolute paths for dbus interface.

Modules/Qt4Macros.cmake

@@ -254,7 +254,15 @@ MACRO(QT4_GENERATE_DBUS_INTERFACE _header) # _customName OPTIONS -some -options
   GET_FILENAME_COMPONENT(_basename ${_header} NAME_WE)
 
   IF (_customName)
-    SET(_target ${CMAKE_CURRENT_BINARY_DIR}/${_customName})
+    if (IS_ABSOLUTE ${_customName})
+      get_filename_component(_containingDir ${_customName} PATH)
+      if (NOT EXISTS ${_containingDir})
+        file(MAKE_DIRECTORY "${_containingDir}")
+      endif()
+      SET(_target ${_customName})
+    else()
+      SET(_target ${CMAKE_CURRENT_BINARY_DIR}/${_customName})
+    endif()
   ELSE (_customName)
     SET(_target ${CMAKE_CURRENT_BINARY_DIR}/${_basename}.xml)
   ENDIF (_customName)