Missing Files After A Slackpkg Install of Sendmail

In the past when building a new server I have used various means of installing software that is not included in the Slackware full install. In doing my most recent build I tried using the command slackpkg" for the first time and for my first install I installed sendmail-8.15.2-x86_64-3.txz. My first thought after doing the install was that slackpkg seemed like a quick and easy way of doing installs. Unfortunately, although the supporting files in /etc/mail all seemed to be present, there was no /usr/share/sendmail directory where I would normally find all the build and .mc files for building and modifying sendmail.cf. After not finding them where I would have expected them to be, I did a search of the complete OS partition thinking perhaps the files were in a new location, but that was not the case. They were simply not installed.

I next tried a resinstall, and this time a /usr/share/sendmail directory was created with four different .cf files and a README, but there were still no .mc files or cf sub-directories. Repeating the reinstall a third and fourth time did not help.

Have I done something wrong or am I expecting too much from slackpkg?