try {
javax.xml.ws.Holder<String> objectId = new javax.xml.ws.Holder<String>();
javax.xml.ws.Holder<CmisExtensionType> portExtension = convertExtensionHolder(extension);
port.createFolder(repositoryId, convert(properties), folderId, policies, convert(addACEs),
convert(removeACEs), portExtension, objectId);
setExtensionValues(portExtension, extension);
return objectId.value;