How can I test that my spam blocks are working?

The -bh option allows you to run a testing SMTP session as if from a given IP address. For example,

exim -bh 192.168.178.39

In addition to the normal SMTP replies, it outputs commentary about which tests have succeeded or failed. If you are not interested in the details, but just want to know if a particular sender at a particular IP address is able to mail to a particular recipient, you can use the exim_checkaccess utility, which provides a packaged > version of -bh. You call it like this:

exim_checkaccess 192.168.53.23 [email protected] -f [email protected]

If you don't give a sender, <> is used (that it, it acts like a bounce message).