It seems that someone installed (a newer) sendmail from source code which was later overwritten by an operating system patch which installed an older one by the system vendor. You have two choices:
As root cp /dev/null mailstats so that you can start measuring again
It seems that someone installed (a newer) sendmail from source code which was later overwritten by an operating system patch which installed an older one by the system vendor. You have two choices:
cp /dev/null mailstats
so that you can start measuring again