How can I serialize an ASP.NET User Control?

I am programmatically adding user controls from an .ascx file into my application on Page_Load, which is necessary because the controls are populated with a database query and the query may return the need for any number of controls to be added.  I want to maintain these controls in the ViewState so that on post-back I can re-add the objects while maintaining the updated values from any changes a user might have made (selecting an item from a drop-down, for example).  When I try to add these controls to the ViewState, however, I get the following exception, which basically tells me that the Serializable attribute is not applied to my control's class:
System.Runtime.Serialization.SerializationException: Type 'ASP.MyClass' in Assembly 'App_Web_pf3y4e1h, Version=0.0.0.0, Culture=neutral, PublicKeyToken=null' is not marked as serializable.

If this were a standard vb class, then I would simply apply the <Serializable()> attribute just before the class declaration, but here the class declaration is implicit in the first line of the file:  
<%@ Control Language="VB" ClassName="MyClass" %>

I have accomplished my ultimate goal here before by manually creating a hashtable object with each of the properties of the control, and then manually re-adding the controls on post-back.  This, however, seems inefficient, since I already have an object to house this data.  How can I apply the Serializable attribute to my control?