Mirrored domains, only one blocks incoming spam. Why?

I have two domains for my company email set up on dreamhost, and I am using the “mirror” domain setup for these. Let’s say these two domains are


(I bought the shorter domain a year or so after I got the original one.)

So I have both set up to block and quarantine and all that, and it works great for stuff coming in to dave@abccompany.com but most of my email (and by far, most of my spam) comes in to dave@abc.com and it is not blocked.

I look at the headers and it appears that it is using the default 999 settings for the abc.com address even though I have double-checked the dreamhost cp settings and both domains are set identically, to a value of “4”.

Will I need to un-mirror these and set each up alone? Or am I missing a check box somewhere.

Thanks for any help or experience that the group might have!


Here is one header showing the problem, real spam, to dave@abc.com:

X-spam-status No, score=4.647 tagged_above=-999 required=999 tests=[HTML_MESSAGE=0.001, MPART_ALT_DIFF=2.246, RDNS_NONE=2.399, TVD_PH_BODY_ACCOUNTS_PRE=0.001] autolearn=disabled

Here is the same header from my home address, to the other incoming address:

X-spam-status No, score=0.012 tagged_above=-999 required=4 tests=[HTML_MESSAGE=0.001, MIME_BASE64_BLANKS=0.001, T_DKIM_INVALID=0.01] autolearn=disabled