function	choix_theme(id_theme){
	
	url = location.href;
	stopIndex = url.indexOf("?");
	
	if(stopIndex != -1){
		url_sans_param = url.substr(0,stopIndex);
	}else{
		url_sans_param = url;
	}

	redirect = url_sans_param + "?";
	
	if(id_theme.value != "" && id_theme.value != 1){
		redirect += "id_tag=" + id_theme.value+"&";
	}
	
	this.location.href = redirect+"page=0";
}