var originalSearchValue;

Event.observe 
(
 	window,
	'load',
	function ()
	{
		var searchBoxElements = $$ ('.search-box');
		
		if (searchBoxElements.size () > 0)
		{
			searchBoxElements.each ( function (searchBox)
			{				
				Event.observe
				(
					searchBox,
					'focus',
					function ()
					{
						if (! originalSearchValue)
						{
							originalSearchValue = searchBox.value;
						}
						
						if (searchBox.value == originalSearchValue)
						{
							searchBox.value = '';
						}
					}
				);
				
				Event.observe
				(
					searchBox,
					'blur',
					function ()
					{
						if (searchBox.value == '')
						{
							searchBox.value = originalSearchValue;
						}
					}
				);
			});
		}
	}
);