diff --git a/index.js b/index.js
index 509e36f..5d3daa0 100644
--- a/index.js
+++ b/index.js
@@ -21,7 +21,7 @@ function makeLogLevel(self, level) {
     if (typeof msg === 'string') {
       self.emit(level, format.apply(null, arguments));
     } else {
-      self.emit.apply(self, arguments);
+      self.emit.apply(self, Array.prototype.slice.call(arguments));
     }
   };
 }