diff --git a/mozilla/xpcom/base/nsISupports.idl b/mozilla/xpcom/base/nsISupports.idl
index 0b0237fc62a..a5d2d0ed091 100644
--- a/mozilla/xpcom/base/nsISupports.idl
+++ b/mozilla/xpcom/base/nsISupports.idl
@@ -41,7 +41,7 @@
  */
 
 /* In order to get both the right typelib and the right header we force
-*  the 'real' output from xpidl to be commentout out in the generated header
+*  the 'real' output from xpidl to be commented out out in the generated header
 *  and includes a copy of the original nsISupports.h. This is all just to deal 
 *  with the Mac specific ": public __comobject" thing.
 */