Need help on mail( SUN OS4 Release 3.5)

[Jialin li]

Hi, we have a SUN 3/60 and want to set it up as a local
mail host. The OS is SUNOS4 Release 3.5. The only experience
I had with mailer is to setup a Sparcstation2, and there are
shared library fixes(for get_host_by_name), sendmail.cf
and sendmail.mx fixes available for OS 4.1.1. 

Can anyone show me where to get mail fixes for that particular
OS version, or what to do? So far, I can send a mail out,
without domainname attached( if the receive end is not
running yp, the sender's IP # is attached).

I am not experienced with this thing, any help/advice
will be greatly appreciated.

Thanks,

Jialin