function checkMail(form) {

var emailAdres = form.email.value;
valid = new RegExp("^[a-z]+([.]?[a-z0-9_-]+)*[@]([a-z0-9_-]+[.])+([a-z]{2,4})$").exec(emailAdres);
if(!valid) { 
   alert( "Please enter a valid email address" );
   form.email.focus();
   return false;
}

return true;

}


function popup(page) {
OpenWin = this.open(page, "popupwindow", "toolbar=no,menubar=no,location=no,scrollbars=no,resizable=yes, height=420, width=600 ");
}


function checkform ( form )
{
    if (form.name.value == "") {
        alert( "You didn't enter a name" );
        form.name.focus();
        return false ;
    }


   var emailAdres = form.email.value;
valid = new RegExp("^[a-z]+([.]?[a-z0-9_-]+)*[@]([a-z0-9_-]+[.])+([a-z]{2,4})$").exec(emailAdres);
if(!valid) { 
   alert( "Please enter a valid email address" );
   form.email.focus();
   return false;
}    

    if (document.contactf.subject.options[document.contactf.subject.selectedIndex].value == "") {
        alert( "You forgot a message subject" );
        form.subject.focus();
        return false ;
    }
    if (form.messagemail.value == "") {
        alert( "You didn't write a message" );
        form.messagemail.focus();
        return false ;
    }

        return true ;
	
}