categories and outlook2007 tasks

hello...

I've got problem with categories in outlook2007/2003 running on
exchange2007 .
When I create task, select category and assign this task to user, he
got
mail for accepting. After accepting task assigned user cant see
category selected in original task. Task creator can can see category
of assigned task corectly.

I've read some issues about managing this over GPO (enable
managing ....) and turn it to enabled state.
But this doesn't help me.
I read, exchange2007 delete categories from emails by default, but I'm
not sure, if in tasks too.

Can somebody help me with this problem ?

Thank you.