None. Why should you ban someone because he played on a bugged server? As long as he didn't buy anything with the qi he got, it doesn't matter.
Do you realize that it was no common server? It was a 3.2 testserver with CIRCULAR dojo and timed dq D:

Ban seems excessive. Punishment is supposed to deter from repeat offenses, where it is clear that the person is not a contributor to society. As in for double client, you get kicked. Second time is ban, right? So what's the minimal amount to deter someone from this? And since it's a recently introduced glitch, how is anyone supposed to know what the rules are? An item reversal is enough, and post-"crime" ban is a rule is made after the fact, so it shouldn't happen that way.

ok so somebody used the Qi bug to purchase items = 4 week ban?

Truth to tell I purchased 2 Pure Bloods, 2 Pure Forces, 2 Pure Relaxs just to share with my friend (but item was locked). I dont want to be banned, so, please, take all pure items back, and give me a refund. I am honest, so I rely on honesty of admins.

see now why would you even think about doing that...

did you honestly think you would be able to keep this stuff because of a just glitch?

Take mine to I just dont want banned

It's called ex post facto. You can't make a rule and call out people for infractions before the rule was made.
But since this is a game, actions can be reverted by authorities. A ban is excessive, just revert what's been done. That's what happened with the Qi already. Everyone in who played that server wasn't banned because the action was reversible, and so are illegitimate items.

The people who used this glitch to buy all the stuff they didn't deserve better get it taken away....

I didn't play 10k matches just for some stupid bug to make people who don't deserve pure/elf/demon to get them..

How about just announce that anyone who got items can PM veb or whoever within a week and they'll be reimbursed. Anyone who is found to have such items when they ought to not have them after the deadline shall just simply have them removed.

Less work for the admins, more work for the people who are passionate about these troubles.

I was one of the moderators there trying to fix the issue.
First of all, the amount of people there just to abuse it was depressing. I even changed the kick server to aikido for all the people "just there to play judo." Only 2 people showed up.
Second of all, how can you expect to get away with it. The abuse of a glitch is a big deal, especially when you know you are doing it, and what you can do with the abuse. I hope all the items bought from people abusing the glitch get their items taken care of. Several people, I will not mention the names, even admitted they were just there to do that.

By the way, if you happen look at my inventory, you'll notice my pure. That is not from glitch abuse. They were given to me by veb.