diff --git a/dovecot.conf b/dovecot.conf
index 6934a11..bc86867 100644
--- a/dovecot.conf
+++ b/dovecot.conf
@@ -15,6 +15,7 @@
 # Values:  TEXT
 #
 failregex = dovecot: auth-worker\(default\): sql\(.*@.*,<HOST>\): Password mismatch
+	    dovecot: auth-worker\(default\): sql\(.*@.*,<HOST>\): unknown user
 
 # Option:  ignoreregex
 # Notes.:  regex to ignore. If this regex matches, the line is ignored.