Redmine

Well you normally should see just those categories which are defined in your project configuration?

Which version of Redmine do you use? Maybe you need some update?

In 2.1.2-devel, this is implemented as requested.

Example:
- ProjectA
-- CategoryA
-- CategoryB
- ProjectB
-- CategoryC
-- CategoryD

You just can see categories A and B in ProjectA and categories C and D in ProjectB.

If you mean something different, please reply on this Ticket. For now, i would say this is already implemented.