Yes, that definitely sounds like the fella needs more water! You can make or buy a dripper. I used to use a plastic cup with a tiny hole in the bottom as a dripper. I found that it puddled on the screen a lot so I got a "Little Dripper" with the valve and it works just fine. All you need is a catch basin for overflow (be sure to empty daily so bacteria and fungus do need settle in) and have it drip on a leaf so he can drink. Watch his behavior and see if he has a preferred spot for it. Luna's is in a corner with lots of foliage so she sort of hides and takes a shower or gets a drink. If it has run out and she is thirsty I will find her there looking up and then at me to say "Hey, how come it's not raining?" LOL!
Lighting question: when you say 100 watt repti bulb I am not sure what you mean. A mercury vapor bulb or is that just for basking?
Supplements. Don't know the ingredients of Reptivite w/o looking it up but you need a calcium supplement as well. It is VERY IMPORTANT. So the water is an issue but your supplementation for a young cham is crucial, too. Here is a site to go to and read the articles on calcium, label ingredient and others on nutrition
also check out this article on MBD:
http://webhome.idirect.com/~chameleon/feature/
chamnews
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0.1 veiled - Luna
0.2 house geckos - Gaia & Tia (both MIA 
0.2 felines - Kyndra and Líta
1.0 African Clawed Frog (for summer)
0.5 Mad. Hissers (for summer - all girls, no little ones, whew!)