In Ubuntu there was always the possibility to change the Main Menu. It was possible to add new items, remove exiting one, move an Item / Application from one Menu to an other and so on.
To change this, there was a tool located under the System ->Preference Menu called „Main Menu“. This is not installed on RHEL6 by default.
You can install that tool via yum, it is named „alacarte“
sudo yum install alacarte
After the installation it is available in the location mentiond above (System -> Preferences).
You can add new Items. I had some issues on adding new Items to already defined Folders / Menu. A workaround for that is to create a new „Folder“ inside the Menu Structure and add the new item to that folder. After that, you can move the new Item to the menu where you want to have it and make the temporary menu / folder invisible.