Theres a little plastic clip in the bag you hook the bladder over, no idea if its compatible with a camelback though.
I really like the bag, and the bladder is excellent (very easy to use and to clean, looks easier than camelback, but I've not tried one), but agree that the bite valve is pants.
What valve are people using as a replacement?
Oh and I managed to snap the clip off my bladder after about 2 weeks. That was my own fault though.