System Center Operations Manager 2007 SMS Management Pack
Boy, not much gets by me. Here's the lesson before I tell the tale: Read The Management Pack Guide. Then read it again.
Right there in the MP Guide for the SMS MP it says:
"To specify the location of the SMS installation folder the script uses a system environment variable on the SMS site server. The administrator must create the %SMS_INSTALL_DIR_PATH% environment variable as a system environment variable so that the MOM Agent running under any user context has access to the log files. The script will then look in the %SMS_INSTALL_DIR_PATH%\Logs directory for the sender.log and distmgr.log files. For more information about setting system environment variables, see the system environment variable web page (<http://go.microsoft.com/fwlink/?LinkId=92316>).
In order for the MOM Health Agent to use this system environment variable the SMS Site Server may need to be restarted."
So if you install SMS somewhere other than C:\SMS, the MP is broken. And I knew that all of my sites would be installed on D:. So I took care of that before installing the management pack, right? Not.
It's easy enough to set a System Variable on the main site server. But what if you have multiple sites? I feel bad enough with forty or so, but know some folks have hundreds to manage. It appears a quick reg hack can take care of it, but then I found this post over on the MSDN blogs. A quick SMS app to install this to all of our site servers, and no more 31705 warnings in the Ops Manager event log.