Minecraft crashing upon opening inventory, chests, menus and pausing.

Unable to pause the game, open the inventory, open chests, initiate chat, or do anything that causes another interface to open over the game.

This causes the game to freeze for a few seconds, then produces a crash report, which I have attached.

This is on a completely fresh copy of Minecraft, with no mods, and on both SMP and single-player.