Strange Behavior of Invalid postback or callback argument. Event validation is enabled using <pages enableEventValidation

I dont get the error when my development database is active

The production database gives the error, the only difference is DATA !!! How possibly can this happen ?

Invalid postback or callback argument. Event validation is enabled using in configuration or <%@ Page EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManager.RegisterForEventValidation method in order to register the postback or callback data for validation.

I did run into a similar issue with the Cascading Dropdowns. Here are various ways into solving this issue:

1. Create a derived class for the dropdownlist as done here
2. The detailed info can be found here

I hope that it will help