Element wsseSecurityElement = document.createElementNS(WSSE_NAMESPACE, "Security");
Element wsuTimestampElement = document.createElementNS(WSU_NAMESPACE, "Timestamp");
wsseSecurityElement.appendChild(wsuTimestampElement);
Element tsCreatedElement = document.createElementNS(WSU_NAMESPACE, "Created");
tsCreatedElement.setTextContent(sdf.format(created));
wsuTimestampElement.appendChild(tsCreatedElement);
Element tsExpiresElement = document.createElementNS(WSU_NAMESPACE, "Expires");
tsExpiresElement.setTextContent(sdf.format(expires));