diff --git a/lib/log.js b/lib/log.js
index 7b1cf5e..ef7a43e 100644
--- a/lib/log.js
+++ b/lib/log.js
@@ -56,7 +56,7 @@ if (!log) {
       var color = colorMap[severity] || colorMap['default'];
       cursor[color]();
 
-      message = message.replace(/\n/g, '\n' + new Array(maxLenSeverity + maxLenSource + 6).join(' '));
+      message = (message || '').replace(/\n/g, '\n' + new Array(maxLenSeverity + maxLenSource + 6).join(' '));
       
       if (methodName !== 'write') {
         source = source || loggerName || getApplicationName();