Back in December '08 I blogged about an article by B. Rubin and A. Rashid [link will be added later] that advocated setting up a UN contact group to facilitate dialogue between India and Pakistan on the issues of Kashmir and Afghanistan. They argued that steps toward resolving some of Pakistan's anxieties about its borders (presumably in both the legal and practical senses) could help reduce Pakistan's motives -- or more specifically, the motives of parts of its army and intelligence service -- to support the Afghan Taliban and other militant groups.
Some relevant aspects of the situation, of course, have changed since Dec. '08. For one thing, U.S.-Pakistan relations have deteriorated (in light of the drone campaign and the killing of bin Laden, among other things), and the U.S. has suspended some military aid to Pakistan. But the future of Afghanistan, especially after the last U.S. combat forces have left, remains as much an open question now as it was at the end of '08. Pakistan's connections with the Afghan Taliban, via elements of the army and ISI, have also not ceased, as far as I'm aware. The Kashmir problem remains, of course, unresolved (btw, the UN has had a small military observer, a/k/a peacekeeping, force along the Line of Control since 1949. The UN spent $16 million on it in 2010-11 according to its website). So if the proposal for a UN contact group made sense in Dec. '08, it would seem still to make sense. The UN has a lot on its plate, to be sure, but that in itself is not a good reason for not adding one more item (double negative, sorry).