I have the same problem. I'm a department on a campus and they only add a X-Spam-Score header if the score is >= 5. They've told users they can junk messages if the header exists at all. Zimbra adds this header even if the score is negative.
The salocal.cf.in looks like this:
add_header spam Flag _YESNOCAPS_
add_header all Status _YESNO_, score=_SCORE_ required=_REQD_ tests=_TESTS_ autolearn=_AUTOLEARN_ version=_VERSION_
add_header all Level _STARS(*)_
add_header all Checker-Version SpamAssassin _VERSION_ (_SUBVERSION_) on _HOSTNAME_
I would like to keep the X-Spam-Status header intact:
But not create a X-Spam-Score header if the score is < 5.
X-Spam-Status: Yes, score=9.773 tagged_above=-10 required=6.6
Anyone know how to make that change in spamassassin? I could look into doing it on my edge MTA, but I think that might be messy to try doing selectively.