Prior to releasing my database in a production environment I am
deleting the source code for the stored procedures with the
following statement:

UPDATE RDB$PROCEDURES
SET RDB$PROCEDURE_SOURCE = NULL
WHERE RDB$SYSTEM_FLAG = 0;

If I drop a SP and re-create the same SP the RDB$SYSTEM_FLAG = null
for the SP. I am curious as to why this is happening.

I am using Firebird 1.5 with Database Workbench 2.4.1.4.

Thanks.
-Shaq