function isEmail(field)
{
   //alert("email: " + field.value);
   var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/; 
   //alert("isMail returns: " + (filter.test(field.value)));
   if (filter.test(field.value)) return false;
   else return true;
}

function isEmpty(field) 
{
  //alert("length is: " + field.value.length);
  for(var i = 0; i < field.value.length; i++) {
     var x = field.value.charAt(i);
     if ((x != ' ') && (x != '\n') && (x != '\t')) return false;
     } // end for
     return true;
} // end function empty()

function isNull(field) 
{
  //alert("received: " + field);
  if ((field.value !== null) && (field.value !== "")) return false;
  else return true; 
}

function isZip(field) {
   //alert("zip code: " + field.value);
   var re = /^\d{5}([\-]\d{4})?$/;
   //alert("isZip returns: " + (re.test(field.value)));
   if (re.test(field.value)) return false;
   else return true;
} // end function isZip()


function validate(form) {
var msg = "";
if (isNull(form.name) || isEmpty(form.name) ) msg += "\n please enter your name ";
//if (isNull(form.name) ) msg += "\n isNull() please enter your name ";
//if (isEmpty(form.name) ) msg += "\n isEmpty() please enter your name ";

if (isNull(form.street) || isEmpty(form.street) ) msg += "\n please enter your street address ";
if (isNull(form.company) || isEmpty(form.company) ) msg += "\n please enter your company name ";
if (isNull(form.city) || isEmpty(form.city) ) msg += "\n please enter your city ";
if (isNull(form.state) || isEmpty(form.state) ) msg += "\n please enter your state ";
if (isNull(form.zip) || isEmpty(form.zip) ) msg += "\n please enter your zip code ";
else if (isZip(form.zip)) msg += "\n please enter a valid zip code ";
if (isNull(form.email) || isEmpty(form.email) ) msg += "\n please enter your email address ";
else if (isEmail(form.email)) msg += "\n please enter a valid email address ";


//if (isNull(form.message) || isEmpty(form.message) ) msg += "\n please enter your message ";

if (msg != "") {
alert(msg);
return false;
}
else return true;


} // end function verify()