diff --git a/lib/server/commander.js b/lib/server/commander.js
index a8b978aa..094767b1 100644
--- a/lib/server/commander.js
+++ b/lib/server/commander.js
@@ -22,7 +22,9 @@
         WIN32               = process.platform === 'win32';
     
     exports.getDirContent = function(path, callback) {
-        Util.checkArgs(arguments, ['path', 'callback']);
+        Util.checkArgs(arguments, ['path', 'callback'])
+            .checkType('path', path, 'string')
+            .checkType('callback', callback, 'function');
         
         fs.readdir(path, function(error, names) {
             if (error)