I use the latest cPanel, and I have very big trouble with email filtering (this problem exists in all previous versions as well).

I get tons of russian spam emails containing russian text in subject. So I made email filters via cPanel.

The rules are simple - if subject contains XXX, discard email. XXX is one of russian characters (letters).

I made many rules (using different russian characters in each rule) to make sure russian spam will be rejected, but none of these rules work. What's wrong?