I used greenpois0n to jailbreak my 3GS on 4.2.1, and backed up my sources and packages with PKGbackup. When I went to restore this data, it said everything was restored, and almost all of my apps were restored to my springboard. However, when I went into Cydia trying to download another tweak, all of my packages and sources were gone, and they won't reappear by clicking reload sources (well, because there aren't any to refresh). I tried re-installing my sources, but when I did, cydia crashed out to the springboard. How can I fix this problem? Is there any way? Thanks in advance!!