As of .86 dispelling enchantments works kind of funky for me now in all my games. When you click dispel it doesn't do anything right away. Maybe 30 seconds later (and maybe after closing the enchantment list window too) the spell book pops up with a description of the spell and slightly after that a confirm dialog will ask you if you really wanted to dispell the enchantment. Seems like a multi-threading/queue processing issue. This was working fine in beta 1 so something got changed there.