title: jQuery/UI Auto complete but only allow existing words to be typed in
body: <p>Hopefully I am explaining this correctly, I have a long predefined list of items (products in my db) and I would like the user to be able to type and auto complete a product, however if that product / word is NOT in the list, I don't want to allow additional characters to be typed.  So the auto complete would ideally block additional input if that input does not exist in the list.</p>
  
  <p>Does something like that exist for the current jQuery UI / jQuery plugin? Or are there mods? I wish to use this method to speed up product selection, but not return a 'not found' page if someone types in something else.</p>
  
  <p>Thank you in advance :)</p>