function checkEmail(email) 
{   
   var filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
   
   if(!filter.test(email)) 
   {
      return false;   
   }
   return true;
}


function removePObject()
{
   $('#newsletterBox form p.success').remove();
}


function validateEmail(obj)
{
   mailInput = obj.find('#mailAddress');
   if(checkEmail(mailInput.val()))
   {
      return true;
   }
   else
   {
      removePObject();
      mailInput.parent().before('<p class="success">Email is invalid please write correct email</p>');
      return false;
   }   
}


$(document).ready(function(){
   
   $('#newsletterBox form').submit(function() {
      
      return validateEmail($(this));
      
   });
});