function correctPNG() // correctly handle PNG transparency in Win IE 5.5 & 6.
{
   var arVersion = navigator.appVersion.split("MSIE")
   var version = parseFloat(arVersion[1])
   if ((version >= 5.5) && (document.body.filters)) 
   {
      for(var i=0; i<document.images.length; i++)
      {
         var img = document.images[i]
         var imgName = img.src.toUpperCase()
         if (imgName.substring(imgName.length-3, imgName.length) == "PNG")
         {
            var imgID = (img.id) ? "id='" + img.id + "' " : ""
            var imgClass = (img.className) ? "class='" + img.className + "' " : ""
            var imgTitle = (img.title) ? "title='" + img.title + "' " : "title='" + img.alt + "' "
            var imgStyle = "display:inline-block;" + img.style.cssText 
            if (img.align == "left") imgStyle = "float:left;" + imgStyle
            if (img.align == "right") imgStyle = "float:right;" + imgStyle
            if (img.parentElement.href) imgStyle = "cursor:hand;" + imgStyle
            var strNewHTML = "<span " + imgID + imgClass + imgTitle
            + " style=\"" + "width:" + img.width + "px; height:" + img.height + "px;" + imgStyle + ";"
            + "filter:progid:DXImageTransform.Microsoft.AlphaImageLoader"
            + "(src=\'" + img.src + "\', sizingMethod='scale');\"></span>" 
            img.outerHTML = strNewHTML
            i = i-1
         }
      }
   }    
}
window.attachEvent("onload", correctPNG);

function showHide()
{

  if (document.forms.contactForm.contactMeBy[0].checked == true)	
  {
    divToShow = "email";  
  }
  else if (document.forms.contactForm.contactMeBy[1].checked == true)	
  {
    divToShow = "telephone";  
  }
  else
  {
    divToShow = "none";  
  }
  

  if (divToShow == "email")
  {
	document.getElementById('telephoneNumber').style.display="none";
	document.getElementById('emailAddress').style.display="block";
  }
  else if (divToShow == "telephone")
  {
	document.getElementById('emailAddress').style.display="none";
	document.getElementById('telephoneNumber').style.display="block";  
  }
  else
  {
	document.getElementById('telephoneNumber').style.display="none";
	document.getElementById('emailAddress').style.display="none";
  }
}

function checkForm()
{
  if (document.forms.contactForm.realname.value == "")
  {
    alert ('Please enter your name.');
    document.forms.contactForm.realname.focus();
    return false;
  }
  else if ((document.forms.contactForm.contactMeBy[0].checked==false) && (document.forms.contactForm.contactMeBy[1].checked==false))
  {
    alert ('Please tell us how you\'d like us to contact you.');
	document.forms.contactForm.contactMeBy[0].focus();
	return false;
  }
  else if (document.forms.contactForm.contactMeBy[0].checked)
  {
	if (document.forms.contactForm.email.value == "")
	{
	  alert ('Please enter your Email address.');
	  document.forms.contactForm.email.focus();
      return false;
	}
	else if (checkEmailAddress(document.forms.contactForm.email.value) == false)
	{
      alert ('Please enter a valid Email address.');
	  document.forms.contactForm.email.focus();
    return false;
	}
  }
  else if (document.forms.contactForm.telephone.value == "")
  {
    alert ('Please enter your telephone number.');
	  document.forms.contactForm.telephone.focus();
	      return false;
  }
  else if (document.forms.contactForm.message.value == "")
  {
	alert ('Please enter your message.');
	document.forms.contactForm.message.focus();
	    return false;
  }
  else
  {
    return true;	  
  }
}

function checkEmailAddress(emailAddress)
{
  var allowed = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789.@-_";
  var emailLength = emailAddress.length;
  var atSignPosition = 0;
  var finalDotPosition = 0;
  var numberOfDots = 0;
  var numberOfAtSigns = 0;

  if (emailLength < 5)
  {
    return false;
  }

  for (i = 0; i < emailLength ;i ++)
  {
    if (allowed.indexOf(emailAddress.charAt(i))<0)
    {
      return (false);
    }
    if ((emailAddress.charAt(i)) == "@")
    {
      numberOfAtSigns ++;
      atSignPosition = i;
    }
    else
    {
      if ((emailAddress.charAt(i)) == ".")
      {
        numberOfDots ++;
        finalDotPosition = i;
      }
    }
  }
  if (numberOfDots == 0)
  {
    return (false);
  }
  if (numberOfAtSigns != 1)
  {
    return (false);
  }
  if (atSignPosition > finalDotPosition)
  {
    return (false);
  }
  if (finalDotPosition == (emailLength-1))
  {
    return (false);
  }
  return (true);
}