the same happend to my a610 if it comes out in 2 pieces you will see by the way the lens is pointing ie,if its pointing up its slipped a cog on the top the only way is to push it down it does take a good bit of strengh but it will go back into place you will feel as though youll damage it but they are strong,it worked for me and would imagine it would be cheaper to buy a new one rather than sending it for repair
brian
December 2010