What temps are your hot and cool spots at? hot spots should be around 95-100 degrees and the cool spots can get around 75-80.
Also, what KIND of UVB light are you using? I recommend the Repti-Sun 10.0 bulb...they last longer and have the strogest amount of UVB output. They are expensive, about $30-$50 depending on where you get it, but more than well worth it.
Also, how high is his basking spot? Another great forum to check out for bearded dragons is this:
http://www.beardeddragon.org/
There are a lot of great people here willing to help.
I hope all goes well. I have two baby beardies and sheesh, they are PIGS...I wish they would take a day's break, haha.