UnboundID LDAP SDK startTLS Error "No extended operation handler"

Question

UnboundID LDAP SDK startTLS Error "No extended operation handler"

An inbound LDAP UnboundID server has been created. The server is listening on an unencrypted port and a TLS port. I can bind it to LDAP on the first port and LDAPS on the second port. However, I cannot connect to it using startTLS. Error:

LDAPException (resultCode = 53 (unwillingness to execute), errorMessage = 'No extended operation handler for extended OID request' 1.3.6.1.4.1.1466.20037 '.', DiagnostMessage = 'No extended operation handler defined for extended OID request' 1.3.6.1. 4.1.1466.20037 '.')

Here's how the server is configured:

 try {
            InMemoryListenerConfig ldapsConfig = InMemoryListenerConfig.createLDAPSConfig("ldaps",
                    LDAPS_PORT,
                    getServerSSLContext().getServerSocketFactory());
            InMemoryListenerConfig ldapConfig = InMemoryListenerConfig.createLDAPConfig("ldap",
                    LDAP_PORT);
            InMemoryDirectoryServerConfig serverConfig serverConfig = new InMemoryDirectoryServerConfig(BASE_DN);
            serverConfig.addAdditionalBindCredentials(BIND_RDN, BIND_PASSWORD);
            serverConfig.setListenerConfigs(ldapConfig, ldapsConfig);
            server = new InMemoryDirectoryServer(serverConfig);
            server.startListening();
        } catch (LDAPException e) {
            fail(e.getMessage());
        }