function checkForm()
{
    var cname, cemail, csubject, cmessage;
   with(window.document.msgform)
   {
      cname    = name;
      cemail   = email;
   }

   if(trim(cname.value) == '')
   {
      alert('Please enter your name');
      cname.focus();
      return false;
   }
   else if(trim(cemail.value) == '')
   {
      alert('Please enter your email');
      cemail.focus();
      return false;
   }
   else if(!isEmail(trim(cemail.value)))
   {
      alert('Email address is not valid');
      cemail.focus();
      return false;
   }
   else
   {
      cname.value    = trim(cname.value);
      cemail.value   = trim(cemail.value);
      return true;
   }
}

function trim(str)
{
   return str.replace(/^\s+|\s+$/g,'');
}

function isEmail(str)
{
    var regex = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;

return regex.test(str);
}