Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_3 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8J2 Safari/6533.18.5)
I use Lockdown Pro. It has the same features including Lock-Delay, so you don't have to enter the passcode everytime you open the app until you put the phone on standby. And also quick-lock: Choose which apps to lock directly from the springboard. I think It was about 2 bucks on Cydia.
There are several other password protection apps worth checking out on Cydia such as: mAdvLock, Locktopus.