People have said it works, I've tried a couple versions from different repos, but they haven't worked for me. If someone knows a specific repo with a working version, I'd like to know. But hopefully the original will be updated soon.
I've been using it for a few days now, i'm not sure what repo it came from but when i checked in cydia, "modmyi" was splashed all over the description. It does work though, haven't had one prob on ip4 4.2.1, yet.
For me iconoclasm has been stable on 4.2.1 since greenpois0n. With redsn0w iconoclasm didn't work, it was always crashing to safe mode, for me at least.