function check_emailsignup() {
    missinginfo = "";
    if(document.emailsignup.FirstName.value == document.emailsignup.FirstName.defaultValue) {
    missinginfo += "\n - Your first name";
    }
    if(document.emailsignup.LastName.value == document.emailsignup.LastName.defaultValue) {
    missinginfo += "\n - Your last name";
    }	
    if ((document.emailsignup.Email.value ==  document.emailsignup.Email.defaultValue) || 
    (document.emailsignup.Email.value.indexOf('@') == -1) || 
    (document.emailsignup.Email.value.indexOf('.') == -1)) {
    missinginfo += "\n - Your e-mail address";
    }
    if (missinginfo != "") {
    missinginfo ="Looks like you forgot to fill in the following:\n" +
    missinginfo;
    alert(missinginfo);
    return false;
    }
    else return true;
}