GREAT !
Thanks @Hawkee !
I was trying to find exactly this autocomplete plugin and I was fighting with a lot of others plugin. Most of the time they don't work or they are nightmares to configure. And when they are OK, they don't work on a textarea displayed on a jquery dialog box :-(
Yours is perfect, light, very easy to use and working into a dialog box !
The only bug was the drop-down list can't be used with the up and down arrows but the hack of @UIdezigner solved that.(I'm using Jquery UI 1.11)