Is there any known issues with Viewstate in ASP.NET 2.0 ?

I have an aspx page with several webcontrols with Viewstate enabled.
I have a button with Javascript to clear a listbox of items selected
which does a Postback checking a Request.Form[] variable and removing items from my list by passing the items back through a Cache[] variable.

However once it is finished, several controls don't have my data in it anymore. It's not all of them which is odd in itself.

Has anyone experienced this or know how to correct it?

Any help would be greatly appreciated.



Thanks,
David

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Thanks,
David