DatePicker Artifact

DatePicker Artifact

I'm seeing an artifact, a light gray horizontal line, on the bottom of a web page where I have two DatePicker controls.

If I hide and then show the two DatePickers then the artifact disappears.

I downloaded and included the latest JQuery in my project.

    <script src="JQuery/jquery-1.4.2.min.js" type="text/javascript"></script>
    <script src="JQuery/jquery-ui-1.8.1.custom.min.js" type="text/javascript"></script>  
    <link href="JQuery/jquery.ui.all.css" media="screen" rel="stylesheet" type="text/css"/> 

I've attached a screenshot of a section of the web page with the datepickers and the artifact.

Ed