Now I have a problem. Got a new iphone on insurance after breaking my other one. Jailbroke it as an tethered jailbreak as I have a 3.1.2 with 5.11.07 baseband however I installed rock then after installing several apps, Rock's disappeared from my iphone and I've tried running blackra1n again to get the blackra1n program back on to install Rock again however no joy!
try with snowbreeze to create ur custom FW where u can choose cydia and rock after that try with shift restore to load the custom FW on ur phone
maybe these could help u