Updating database stored procedure

This seems to work great, except that changes in stored procedures are not reflected when updating or refreshing the model.

Adding a column to a table is reflected, but not adding a field to a stored procedure.

I ended up just renaming the proc and importing via model update from database. Added a new column, and renamed an existing column.

I refreshed the EDMX via update model from database, but there were no changes to the EDMX, and obviously at run time, it fails.

How should a stored procedure update be done with Entity Framework?