The block should be removed. Things said on an IRC channel on freenode are things not said in the wikipedia namespace. Just as emails sent through wikipedia are not covered by wikipedia policy.
I saw what was said between you and Libertas. You said some pretty nasty things as well. You are CLEARLY too emotionally/personally involved to issue a block against Libertas, and it should be lifted immediately. IRC is not part of the wikipedia namespace, no matter what the [[l33t hax0r]] #wikipedia junkies would like to think. It would be an embarrasment to wikipedia.org if it was.
Your last act as an admin should be to get another admin to block you for the exact same time that Libertas was erroneously blocked. Its a shame, since you seem like a nice person, and this may have been an unfortunate lapse.