Changing user wise name(label) of menu item

hi all,

In AP > PO > open any purchase order > purchase tab > journals (action pane) > "purchase order confirmation"  .

this "purchase order confirmation" i want to change to "work order confirmation" for only a particular user .

I had just personalized the form and change the label for it. It worked for first time the name of that menu item button is changed ...but now that changes are not visible on form . is there any other procedure through we can change its name