No. Modules must be compiled with the same SDK as the application that loads them. Modules need to be loaded using ModuleManager.
thanks darrell for replying to my question
if i can not load the flex 3 module in flex 4 application, then
can i load flex 3 swf in flex 4 application using swfloader and inside flex 3 swf application load my flex 3 module?
Loading a Flex 3.2 and greater app into a Flex 4 app is support by a feature called the Marshall Plan. The Marshall Plan is needed by large apps with many subapplications. In Flex 4 the Marshall Plan is an optional feature that is only compiled into an application when you compile with the -includes=mx.managers.systemClasses.MarshallingSupport option.
If your app isn't large then another option for you is to recompile your Flex 3 application using the Flex 4 SDK but compile with the -compatibility-version=3.0.0 option.