How to apply a patch

[Ari Arantes Filho]

Hi All,

    I've download a patch from Chris Johnson to control the envelope sender,
but I don't know how to apply it???

    I would like to understand more about patchs and how to apply, create
one and how it works. Where can I find documentation?

    I would like to apply other patch from "Frank DENIS aka Jedi/Sector One
aka DJ Chrysalis <[EMAIL PROTECTED]>" to truncate the mailer-daemon failure notice,
is it possible to apply 2 or 3 patches? Is there an order to apply them?

Best regards,

Ari