Log Message:
Update from 2.4.3 to 2.4.4.

This is a minor patch reelase, fixing two uncommon crash bugs and tidying
up a couple of things.  One of the crash bugs was introduced in 2.4.3 so
if you're running that version you should consider upgrading.

The formal release notes entry:

2.4.4           2008/01/25
        In mlfi_close(), don't assume the libmilter private context pointer
                is not NULL.
        Fail to start up if told to load a key list which resulted in no
                keys being loaded.
        When "AutoRestart" is in use, the parent will now wait for the
                child to terminate before exiting.  Thus, something that
                signals the process ID in the pid file can also wait on that
                process to be gone before being sure that the service has
                actually shut down.
        Include the job ID when logging about Authentication-Results: headers
                that can't be parsed.  Problem noted by S. Moonesamy.
        LIBDKIM: In dkim_policy(), skip invalid signatures during evaluation
                of step 1 of SSP as the signature handle may not have been
                fully populated.