How do I list all non-system stored procedures?

Question

I want to create a query to list of all user defined stored procedures, excluding the ones that are system stored procedures, considering that:

1. Checking the name like "sp_" doesn't work because there are user stored procedures that start with "sp_".
2. Checking the property is_ms_shipped doesn't work because there are system stored procedures that have that flag = 0, for example: sp_alterdiagram (it is not MSShipped but appears under System Stored Procedures in SQL Server Management Studio).

There must be a property, or a flag somewhere since you can see the "System Stored Procedures" in a separate folder in SQL 2005. Does anyone know?

---

Edit: A combination of the suggestions below worked for me:

select *
from 
    sys.objects             O LEFT OUTER JOIN
    sys.extended_properties E ON O.object_id = E.major_id
WHERE
    O.name IS NOT NULL
    AND ISNULL(O.is_ms_shipped, 0) = 0
    AND ISNULL(E.name, '') <> 'microsoft_database_tools_support'
    AND O.type_desc = 'SQL_STORED_PROCEDURE'
ORDER BY O.name

Answer 1

You should use something like this:

select * from sys.procedures where is_ms_shipped = 0

As you could guess, the key is in is_ms_shipped attribute (it exists in sys.objects view as well).

UPDATED. Initially missed your point about is_ms_shipped.

This is the code (condition) that Management Studio actually uses to retrieve a list of 'system stored procedures'

 CAST(
 case 
 when sp.is_ms_shipped = 1 then 1
 when (
    select 
        major_id 
    from 
        sys.extended_properties 
    where 
        major_id = sp.object_id and 
        minor_id = 0 and 
        class = 1 and 
        name = N''microsoft_database_tools_support'') 
    is not null then 1
 else 0
 end AS BIT) = 1

Here sp refers to sys.all_objects system view.