You are going to need to find some "oomph" for the necklace, and Uldaman is probably the best place for it, actually.  I guess there are a lot of constructs running around in there, yeah?  Well, take out the biggest, baddest construct in that place and grab its power source!  I am pretty sure I can fuse that source into the necklace.$B$BWithout that power source, fixing the necklace will be impossible.  Come back to me here to Ironforge when you have it, and we'll get it all fixed up for you!