diff --git a/src/mail.js b/src/mail.js
index 9ecad0f32..85e52038c 100644
--- a/src/mail.js
+++ b/src/mail.js
@@ -527,7 +527,7 @@ async function checkRblStatus(domain) {
         const [error, records] = await safe(dig.resolve(flippedIp + '.' + rblServer.dns, 'A', DNS_OPTIONS));
         if (error || !records) continue;    // not listed
 
-        debug(`checkRblStatus: ${domain} (ip: ${flippedIp}) is in the blacklist of ${JSON.stringify(rblServer)}`);
+        debug(`checkRblStatus: ${domain} (flippedIp: ${flippedIp}) is in the blacklist of ${JSON.stringify(rblServer)}`);
 
         const result = _.extend({ }, rblServer);