function clearBox(obj)
{
	if ( "search" == (obj.value) )
	{
		obj.value="";
	}
}



function emailCheck (emailStr)
{


    var checkTLD=1;
    var knownDomsPat=/^(com|net|org|edu|int|mil|gov|arpa|biz|aero|name|coop|info|pro|museum)$/;
    var emailPat=/^(.+)@(.+)$/;
    var specialChars="\\(\\)><@,;:\\\\\\\"\\.\\[\\]";
    var validChars="\[^\\s" + specialChars + "\]";
    var quotedUser="(\"[^\"]*\")";
    var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/;
    var atom=validChars + '+';
    var word="(" + atom + "|" + quotedUser + ")";
    var userPat=new RegExp("^" + word + "(\\." + word + ")*$");
    var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$");

    var matchArray=emailStr.match(emailPat);

    if (matchArray==null)
    {
        //alert("Email address seems incorrect (check @ and .'s)");
        return false;
    }

    var user=matchArray[1];
    var domain=matchArray[2];

    for (i=0; i<user.length; i++)
    {
        if (user.charCodeAt(i)>127)
        {
            //alert("Ths username contains invalid characters.");
            return false;
        }
    }

    for (i=0; i<domain.length; i++)
    {
        if (domain.charCodeAt(i)>127)
        {
            //alert("Ths domain name contains invalid characters.");
            return false;
        }
    }

    if (user.match(userPat)==null)
    {
        //alert("The username doesn't seem to be valid.");
        return false;
    }

    var IPArray=domain.match(ipDomainPat);
    if (IPArray!=null)
    {
        for (var i=1;i<=4;i++)
        {
            if (IPArray[i]>255)
            {
                //alert("Destination IP address is invalid!");
                return false;
            }
        }
        return true;
    }

    var atomPat=new RegExp("^" + atom + "$");
    var domArr=domain.split(".");
    var len=domArr.length;

    for (i=0;i<len;i++)
    {
        if (domArr[i].search(atomPat)==-1)
        {
            alert("The domain name does not seem to be valid.");
            //return false;
        }
    }

    if (checkTLD && domArr[domArr.length-1].length!=2 && domArr[domArr.length-1].search(knownDomsPat)==-1)
    {
        //alert("The address must end in a well-known domain or two letter " + "country.");
        return false;
    }

    if (len<2)
    {
       //alert("This address is missing a hostname!");
        return false;
    }

    return true;

}




function chkForm(obj)
{

        var errorMsg = "";

    	if ( "" == obj.contact_forename.value )
    	{
			errorMsg += "  please enter your firstname\n";
    	}

      	if ( "" == obj.contact_surname.value )
      	{
  		errorMsg += "  please enter your surname\n";
    	}

    	if ( !emailCheck(obj.email.value) ) 
	{
		errorMsg += "  please enter a valid email address\n";
	}

	if ( "" != errorMsg )
	{
		alert('The following errors have occurred: \n' + errorMsg);
		return false;
	}

	return true;

}