jQuery Autocomplete help

[tamilsweet]

Hi,
I'm using jQuery autocomplete plugin to fetch data from db.
The demo is at http://test.bambeeq.com/demo/wordpress/college/

I have hidden input field next to each visible field and the hidden field is populated with the id(from database) of the data selected in visible field.
Now, if the field is made empty, the id should be updated to null.
but i'm unable to use .change() or .keypress() eventhandlers because if i use them autocomplete stops working !?

any help would be appreciated!