binmail(1) question

[Tage Stabell-Kul]

I had a problem with the mail.  Sendmail(8) reported "unknown mailer
error 255".  No mail were delivered.
I have found that the mail-delivery program binmail(1) (/bin/mail) requires 
that /dev/kmem have mode 444 (or more)

Two questions :

0) What info does /bin/mail read from kmem ?
1) /bin/mail is setuid-root.  Do the program do a setuid , if so, to
whom ?

|Tage Stabell-Kuloe                  |Fast:     tage at sfd.uit.no              |
|Department of Computer Science,     |Official: postmaster at sfd.uit.no        |
|University of Tromsoe, Postboks 953,|Phone:    +47 8344117                  |
|N-9000 TROMSOE, NORWAY.             |#include <disclaimer.std>              |