A little message in all mails

[J.J.Gallardo]

Hi:

I would like to put a little message (like "Get your own private free
e-mail at xxx.yyy.com), but i have seen:
1) In file sqwebmail-config the program put the message.
2) If this file it's owner by root:vchkpw, then the content is unvisible
for the world.
3) If this file it's owner by vpopmail:vchkpw, then when the user writes
a new messages he can delete this contents.

Is there a solution?

Thanks in advanced.