intLastIssueId = -1;
function changecover( intIssueId ){
	if(intLastIssueId == intIssueId)
		return;
	if(intIssueId != ""){
		try{document.getElementById('IssueCover' + intLastIssueId).style.display = 'none';}catch(e){}
		try{document.getElementById('IssueCover' + intIssueId).style.display = 'block';}catch(e){}
		intLastIssueId = intIssueId;
	}
}