Back in the day, when I got stuck I'd go for a jog. The more stuck, the longer the jog. :)

>First, thank you all for your help!
>
>It is fascinating how a solution very often comes when you get away from the problem. When I posted this question I was in the office working on a very complicated solution. I spent more than an hour testing various approaches. Nothing worked. But I learning some things about jQuery (good thing). Then it was time to go home. While driving home the solution came to me as a very simple and straight forward. So my suggestion: get in the car and drive around when you have an unsolvable problem :)