new 4.5 validation (with data annotations) does not work with formview when using OnItemInserting, but does work when using new binding methods for InsertMethod

I'm using Entity Framework with new data binding validation on my formviews. Initially, I had them set up to use the InsertMethod, but I was having some issues with async tasking to a web service rather than a database, so I changed to the OnItemInserting event. After doing so, my validationsummary control does not work with my class data annotations?? The ModelState.IsValid always appears to 'true' even when the controls have invalid data. Does anyone know what I'm doing wrong? Can I provide example info to help resolve? ...I appeciate any help in advance!