[hobbit] graph support for later sendmail versions

In setting up the sendmail graphs, I found that some fields introduced in later sendmail versions were not displayed.

The attached patch to do_sendmail.c will allow the extra field introduced in sendmail 8.13.x to be graphed. It should also work with most earlier versions of sendmail back to at least 8.9.x (if you're running a version that old, it's time to upgrade!)

As we only run 8.13.x in production, I haven't been able to test much the changes with prior versions of sendmail other than a quick test with 8.11.x.

Regards Geoff Steer Firstwave Technology