Thought I would share with you this useful link which I accidentally bumped into while doing some search on EP. This is useful if you have want to convert Dynamics AX 4.0 Web Forms to the latest Dynamics AX 2009 Web User Controls.
The SysEPWebFomConverter class contains several methods that are used when you convert a Web form from an earlier version of Enterprise Portal to the components used with the ASP.NET-based framework. To use this class, save the text of the export file as an .xpo file. Import the .xpo file into the AOT. For details about how to use the methods in the class to convert Web Forms
How do Convert
Read here, more about the conversion http://msdn.microsoft.com/en-us/library/cc620983.aspx
And at the end you can verify if the conversion succeeded by http://msdn.microsoft.com/en-us/library/cc619852.aspx