Cant get linq to recognize that sproc has changed

I have a GridView that is populated by a stored procedure via linq. I changed the stored procedure to return an additional column, but I can't get the additional column to show up in the GridView. The GridView has autogeneratecolumns=true, so if I were using a SqlDataSource the new column would show up automagically. But now it is not showing up and I cannot reference it. I can't figure out how to make linq recognize that my stored procedure has changed.

I have tried deleting the sproc definition from the dbml file, making sure the partial class is removed the .vb file, refreshing the stored procedures list in database explorer, and adding the sproc definition back again (a hassle), but still it insists on defining only the original columns and not the new column.

How do get linq to get back in sync with the database?

Is there any way to get linq back in sync after database changes??

sql