You can setup a custom filter for good email, so for example, email matched against a particular subject line will bypass the spam filters.

Filters can be either plain text or regular expressions (regular expressions syntax from Regexlab)

When filtering multiple values:
To use OR operator, choose ‘Reg. expression’ and separate each filter value with a pipe e.g.
one|two|three|four

to use AND separate each filter value on a new line. e.g.
One
Two
Three
Four