function changeImg(pos) {
	var imgFullElement = document.getElementsByName("imgFull")[0];
	var imgSmallElement = document.getElementsByName("imgSmall")[pos-1];

	var tmpImg = imgFullElement.src.split("graphik/");
	tmpImg = tmpImg[1].split(".");
	var smallImg = "graphik/" + tmpImg[0]+"_kl."+tmpImg[1];
	tmpImg = imgSmallElement.src.split("_kl.");
	
	imgSmallElement.src = smallImg;
	imgFullElement.src = tmpImg[0]+"."+tmpImg[1];
}

//function to check valid email address
function isValidEmail(strEmail){
  validRegExp = /^[^@]+@[^@]+.[a-z]{2,}$/i;
  strEmail = document.forms[0].email.value;

   	// search email text for regular exp matches
   	if(strEmail!=""){
	    if (strEmail.search(validRegExp) == -1) {
	    	alert('Sie haben eine ungültige E-Mail-Adresse eingegeben.\nBitte überprüfen Sie Ihre Eingabe.');
	    	return false;
	    } 
	    	return true; 
	}
}

Normal1 = new Image();
Normal1.src = "graphik/index_man.jpg";
Highlight1 = new Image();
Highlight1.src = "graphik/index_man_grey.jpg";

Normal2 = new Image();
Normal2.src = "graphik/index_woman.jpg";
Highlight2 = new Image();
Highlight2.src = "graphik/index_woman_grey.jpg";

Normal3 = new Image();
Normal3.src = "graphik/index_video.jpg";
Highlight3 = new Image();
Highlight3.src = "graphik/index_video_grey.jpg";

function Bildwechsel(Bildnr,Bildobjekt)
  {
     window.document.images[Bildnr].src = Bildobjekt.src;    
  }