The problem with your setup is with spamass-milter, not SpamAssassin.
And people exclusively ask questions about SA on here? Never ever one on the milter?
Perhaps I should have been a little more verbose -- I wasn't saying not to ask your question here. It's not a SpamAssassin config issue it's likely a config issue with the spamass-milter.
Your maillog paste doesn't show the Subject: header being modified, it only shows the X-Spam headers being added. This may be a symptom of the '-m' option being present in the call to whatever the spamass-milter executable is.
As for the lack of encapsulation, in the 60 seconds or so of looking through the spamass-milter documentation to find the -m option info, I didn't see any mention of encapsulation -- I don't think it's possible with this milter.
Daryl
