var Search = document.siteSearch.elements["q"];
Search.onfocus=function() {
    var fn = document.siteSearch.elements["q"];
    if (fn.value=="SEARCH") fn.value="";
};
Search.onblur=function() {
    var fn = document.siteSearch.elements["q"];
    if (fn.value=="") fn.value="SEARCH";
};