Sendmail upgrade advice

[Rob]

Hi All,

I had some problems with Sendmail a few weeks ago and it was suggested that
I upgrade. I am finally able to do this but am now experiencing further
problems. I downloaded 8.13 but the instructions just seem to lead me in
circles sending me from one readme to another.

Ok, so it tells me the easiest way to build sendmail is to type sh Build in
the Sendmail directory. I just get an error:

%sh build
build: Can't open build: No such file or directory
%sh Build
Configuration: pfx=, os=FreeBSD, rel=4.4-RELEASE, rbase=4,
rroot=4.4-RELEASE, arch=i386, sfx=, variant=optimized
Using M4=/usr/bin/m4
Creating /usr/home/rob/sendmail-8.13.0/obj.FreeBSD.4.4-RELEASE.i386/sendmail
using /usr/home/rob/sendmail-8.13.0/devtools/OS/FreeBSD
sed: 1: "s/
//g
": unterminated substitute pattern
sed: 1: "s/
//g
": unterminated substitute pattern
ERROR: /usr/bin/m4 failed; You may need a newer version of M4, at least as
new as System V or GNU

I see that it is using M4=/usr/bin/m4 so do I need to perform some sort of
upgrade on that file first?

I also see that the instructions tell me to create any necessary site
configuration build files, as noted in devtools/Site/README. Well this
particular Readme tells me nothing on how to perform these file creations.

I have read through all the readme and install files and just can't seem to
get any further.

Any help really appreciated. I am upgrading from 8.11.6.

Rob.