Created Unassigned: SPAutocomplete clear Input box text [10159]

The scenario is as below

1.When a user types some char in the autocomplete textbox, drop down will be visible with the values.
2.If the user doesnt select any from the dropdown list and moves out of the control then i want to clear the text box as well as the drop down should not be visible. The below is the code

$(document).ready(function () {

$().SPServices.SPAutocomplete({
sourceList: "List1",
sourceColumn: "ListItemName",
columnName: "txtListItem",
ignoreCase: true,
numChars: 2,
slideDownSpeed: 1,
debug: false
});
});

It will be great if you can let me know on how we can achieve the same.

Thanks
Suresh A