Will blackra1n still work?

I have a iPod touch 2g mc model 4.2.1 and I tried everything new to jailbreak it but nothings working.greenpois0n keeps crashing, redsn0w says unable to recognize specified ispw,and limera1n doesn't have the limera1n symbol on my ipod when it says it's finished. It has the apple sighn. So will blackra1n work on it? Because that doesn't seem to have a problem when I open it and everything