JQuery UI Autocomplete and MVC3 Remote Validation Conflict

On a recent project I had a great deal of trouble to get JQuery UI Autocomplete and ASP.Net MVC3 Remote Validation to play nicely with each other. The goal was to have a type-in for selecting a city for a search in which the pull-down would auto-complete based on the available cities in the database: Once a city is selected from the autocomplete it should do a validation as to whether the city is populated with actual data in the database (in case the user types in an invalid city: