Adding custom fields

[Ben]

I work at a company which uses Bugzilla, and they are always asking me
about adding custom fields to Bugzilla, such as the source of the bug
(i.e. internal, from customer, from beta tester, etc.) and various other
such fields.  How difficult would it be to do this, and is there any
accepted procedure or are there any guildlines for doing it?
Thank You,
Ben 
-- 
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