How do I block and not deliver Blacklisted emails?

[Hedley Phillips]

Hi,

I'm blacklisting a few .tld's that are known sources of spam and currently
blacklisted emails are being delivered as High Scoring spam as per these two
settings:

Is Definitely Spam = %rules-dir%/spam.blacklist.rules

Spam Blacklist:
Make this point to a ruleset, and anything in that ruleset whose value is
"yes" will *always* be marked as spam. This value can be over-ridden by the
"Is Definitely Not Spam" setting. This can also be the filename of a
ruleset.

Definite Spam Is High Scoring = yes
Setting this to yes means that spam found in the blacklist is treated as
"High Scoring Spam" in the "Spam Actions" section below. Setting it to no
means that it will be treated as "normal" spam. This can also be the
filename of a ruleset.

I have a customer who has set High Scoring Spam to be delivered to their
spam account as they don't want High Scoring spam to be deleted but also
doesn't want to receive any blacklisted tld's.

Is there a way to block blacklisted emails without marking them as High
Scoring spam and delivering them? 

Thanks