var frmvalidator = new Validator("myform");
 
 frmvalidator.addValidation("epost","req","Ange din e-postadress!");
 frmvalidator.setAddnlValidationFunction("DoCustomValidation"); 
 
 function DoCustomValidation()
{
  var frm = document.forms["myform"];
  if(frm.epost.value == 'Ange din e-postadress')
  {
    alert('Ange din e-postadress!');
    return false;
  }
  else
  {
    return true;
  }
}

 function ResetForm()
{
  var frm = document.forms["myform"];
  if(frm.epost.value == 'Ange din e-postadress')
  {
    frm.epost.value = ''
  }
}

 function SetForm()
{
  var frm = document.forms["myform"];
  if(frm.epost.value == '')
  {
    frm.epost.value = 'Ange din e-postadress'
  }
}