President precedent?

I always thought that Pakistan was a parliamentary democracy (when it was, i.e.) that was similar to India in many respects. The same federal structure, the same judicial structure and the same administrative structure.
So I was surprised when I saw Asif Ali Zardari visit Washington and address the UN as the head of state. I was under the impression that like India, the PM was the head of state for all practical purposes while the President was a titular head.
Did the constitutional changes that Musharraf made, also include the clause that the Pres will have greater authority than the PM? Haven't they rolled back those changes?
Or not as yet?