i solved the prob.
to those who have the same prob, here is how i solved it.
first enable chooser at login.
and when you log in give a new name for the session. here you can enable 'allow xfce to manage desktop' and disable choose session at startup. save settings at logout.
re log in.
now it should work
:) ~~~~PrOuDtoBeALiNuxUsEr~~~~ :)