function replaceContent(url, targetContainer) {
    var request = null;
	if (window.XMLHttpRequest) 
		request = new XMLHttpRequest();
	else if (window.ActiveXObject)
		request = new ActiveXObject("Microsoft.XMLHTTP");
	if (request) {
		request.open("GET", url, false);
		request.send(null);
		if (request.status == 200) {
			var content = request.responseText;
			var tagHtml = document.getElementById(targetContainer);
			tagHtml.innerHTML = content;
		}
	}	
}

function removeTag(tag, messageID, targetContainer) {
	var url = "tags!remove.jspa?tag="+escape(tag)+"&messageID="+messageID;
	replaceContent(url, targetContainer);
}

function addTags(tagList, messageID, targetContainer) {
	var url = "tags!add.jspa?tagList="+escape(tagList)+"&messageID="+messageID;
	replaceContent(url, targetContainer);
}

function clearTagInput(tagInputId) {
	document.getElementById(tagInputId).value = '';
}