Okay, I've just had a look..apologies for the lame naming!

CREATE SCHEMA dba

CREATE ROLE schema_test

GRANT EXECUTE ON SCHEMA::dba TO schema_test

CREATE PROCEDURE dba.Test_Schema

AS SELECT * FROM dbo.MyTestTable

When I view the permissions on the stored procedure it doesnt show anything for the role but on the schema the EXECUTE permission for the role shows correctly, this should be cascaded down through to the objects the schema contains.

I tested earlier on a user added to the role and it appeared to be working.