diff --git a/mime.js b/mime.js
index 341b6a5c..cbe0e938 100644
--- a/mime.js
+++ b/mime.js
@@ -22,9 +22,9 @@ Mime.prototype.define = function (map) {
   for (var type in map) {
     var exts = map[type];
     for (var i = 0; i < exts.length; i++) {
-      if (process.env.DEBUG_MIME && this.types[exts]) {
-        console.warn(this._loading.replace(/.*\//, ''), 'changes "' + exts[i] + '" extension type from ' +
-          this.types[exts] + ' to ' + type);
+      if (process.env.DEBUG_MIME && this.types[exts[i]]) {
+        console.warn((this._loading || "define()").replace(/.*\//, ''), 'changes "' + exts[i] + '" extension type from ' +
+          this.types[exts[i]] + ' to ' + type);
       }
 
       this.types[exts[i]] = type;