var change_back = 0;

function showPic (whichpic, i) {
	if (document.getElementById) {
  		document.getElementById('image').src = whichpic.href;
		//remove all caption content
		var len = document.getElementById('caption');
   		while (document.getElementById('caption').hasChildNodes()){
	  		document.getElementById('caption').removeChild(document.getElementById('caption').firstChild);
		}
		//create new caption
  		if (document.getElementById('caption_content_'+i)) {
			var len = document.getElementById('caption_content_'+i).childNodes.length;
			for(var j = 0; j < len; j++){   
      			document.getElementById('caption').appendChild(document.getElementById('caption_content_'+i).childNodes[j].cloneNode(true)) ;
   			}
		}
		//replace all thumbnails with originalthumbnail
		if (change_back != 0){
			var source = document.getElementById('thumb_'+change_back).src;
			document.getElementById('thumb_'+change_back).src = document.getElementById('thumb_hover_'+change_back).src
			document.getElementById('thumb_hover_'+change_back).src = source;
		}
		if (document.getElementById('thumb_hover_'+i)) {
			var oldsource = document.getElementById('thumb_'+i).src;
			document.getElementById('thumb_'+i).src = document.getElementById('thumb_hover_'+i).src;
			document.getElementById('thumb_hover_'+i).src = oldsource;
			change_back = i;
		}
		return false;
 	} else {
 	 	return true;
 	}
}