I just use plastic epoxy that you can also pick up at a auto store.

the stuff is a heck of allot stronger then any superglue that i have found, heck you can even use it to fabricate parts (like you can do with bondo on a car). its great stuff to use.

there is also different mixes for glass, wood, and metal, and PVC and so on. if you ask me this is the JB weld for plastic (you also don't have to worry about it drying dark either).