Pakistan has admitted that some of it's senior nuclear weapons scientists have sold atomic bomb designs to other countries (Libya, North Korea and Iran were most often mentioned.) It was long suspected that Pakistan was trading nuclear weapons technology to other countries for cash (Iran) or missiles and missile technology (North Korea.) The Libyan connection only became known when Libya recently agreed to dump all its weapons of mass destruction programs and go straight (and get out from under sanctions and other penalties for being considered a threat to world peace.) Pakistan insists that there was no government involvement with these deals, that it was just some scientists corrupted by a large payoff. Corruption in Pakistan has long been a major problem, and that makes the "corrupt scientists operating on their own" story seem possible. But there's all that other evidence of Pakistani aircraft and ships carrying mysterious cargoes to North Korea and Iran. This points to Pakistani government involvement. What was the cargo? Well, to make an atomic bomb requires more than plans, technical manuals and consulting services from corrupt scientists. There's a lot of engineering equipment needed to actually build a working nuclear weapon. Some of this stuff, that is also used for more peaceful purposes, can be purchased openly. But some of it is custom made, and a lot of it is not the kind of stuff a corrupt scientist can smuggle out in the trunk of his car. Making an atomic bomb is a major project, requiring the efforts of thousands of scientists, engineers, skilled technicians and craftsmen. Take a close look at the steps required to build an atomic bomb and you realize that "help" requires more than some documents and advice from a scientist who has already built a bomb that works. 

It's been big news in Pakistan for months that some key nuclear scientists were being questioned by the police. Something is up. It's quite possible that the scientists cut their own deals, on the side, so to speak, with nations that had already agreed to buy Pakistani nuclear weapons technology. Then again, Pakistan is noted for independent minded and free wheeling government departments. In particular, ISI (the local CIA) has long been known for operating on its own, and getting away with it. Who knows? Right now, no one. Including many in the Pakistani government.