Wrong appearance date on ticket..?

Friend got a misdemeanor ticket for no proof of insurance 5/4/08 the date to appear or take care of it on the ticket was by 5/22/08 at 9 am.
He had a warrant for his arrest on May 15th, and was arrested May 19th when he tried to take care of it, paid the money to get out of jail after a couple hours.
I believe the ticket should have said 10 days to take care of it. Where does he stand, was this a false arrest since he didn't technically do anything wrong according to the way the ticket was wrote? How do you fight this. Shouldn't this be thrown out since it was wrong?
From what I understand the prosecutor said he would drop it to a civil infraction and just pay a fine. And they would also keep the $260.00 he paid to get out of jail. I think it should all be dropped since he did have insurance and he acted before the date on the ticket and should have never been arrested. There was no change of date and all records show it has 5/22/08 on the ticket.

At the very least make it a civil infraction and let him use the money from the get out of jail money towards the ticket and no record.

An incorrect date on the ticket does not invalidate the charge against him. He's still guilty of not having proof of insurance.
False arrest would require proving gross negligence or willful misconduct. That's probably not going to happen in this case.
It does seem to me, however, that the ticket with the wrong date should provide proof of extenuating circumstances, and should be cause to let him get away with paying the original fine only. The $260 bail should be returned to him or credited to the fine. Of course, that's just my opinion and they rarely use my opinion as a legal precedent.

Not sure what state your in. When wrote a ticket it says to contact clerk at # .You can find out info. of ticket etc.. You will have to answer ticket how you plead and mail in. I assume someone got crossways. Just pay an be done with it.