Having network problem after rooting to 2.3.5?

Software: 2.3.5
HTC Sense Version: 3.5

(Software info above)

I rooted and download a custom rom (runnydroidv2.1) on my HTC inspire. I am happy with the platform, but I am somehow unable to turn off mobile network. Everytime my inspire phone goes on stand-by/sleep and I turn it on, both the wifi and mobile network is on (checked). I am trying to figure out how to make the mobile network shut off (unchecked), untill I turn it on manually. Is there a way I can do this???