Dude... I also came through certain situation.
But the only change in my case is, it was checklistbox.
If I am not wrong, you must facing problem like,
On selection of list value you need the current selectedvalue,
but you must be getting the first selected value on every selection change...
If this is your problem, I have made a solution for checklistbox on my blog
You can refer the same, only by changing my checklistbox to listbox