function validate(form) {

    if (! isEmailAddr(form.email.value) )
    {
        alert("Please enter a valid e-mail address.")
        form.email.focus()
        return false
    }

    if (form.email.value.indexOf("@") == -1)
    {
        alert("Please enter a valid e-mail address.")
        form.email.focus()
        return false;
    }

    if (form.zip.value.length == 0) 
    { 
        alert("Please enter your zip code.") 
        form.zip.focus() 
        return false 
    } 

    if (form.fname.value.length == 0) 
    { 
        alert("Please enter your first name.") 
        form.fname.focus() 
        return false 
    } 
    if (form.lname.value.length == 0) 
    { 
        alert("Please enter your last name.") 
        form.lname.focus() 
        return false 
    } 

}

function isEmailAddr(email)
{
  var result = false;
  if (email.length > 3)
  {
    var theStr = new String(email);
    var index = theStr.indexOf("@");
    if (index > 0)
    {
      var pindex = theStr.indexOf(".",index);
      if ((pindex > index+1) && (theStr.length > pindex+1))
        result = true;
    }
  }
  return result;
}