How is your organization inactivating eSupplier User?

We currently have single sign on through Identity and Access Management but the way we have it set up our suppliers can't currently be inactivated. We were thinking of putting a new field on the Define Supplier User page for User Status and have our Identity and Access management read that field to determine whether the person should have access. We looked at the account locked button but when you select that nothing happens in the Security User profile page the reflects the account locked out button on define supplier user page has been checked.