error ZcChat , 1.21

hello upgrade to the latest version and now when I want to send a chat I get this error

ZeXtras Error
Unknown Exception {exception}
Client: User Interface
At time 1414430090624
Unknown Exception {exception}
at Object.printStackTrace.implementation.createException ( Zimlets-nodev_all.js.zgz:3699 )
at Object.printStackTrace.implementation.run ( Zimlets-nodev_all.js.zgz:3690 )
at Unknown.printStackTrace ( Zimlets-nodev_all.js.zgz:3684 )
at ZxError.createStackTrace ( Zimlets-nodev_all.js.zgz:2190 )
at Unknown.new ZxError ( Zimlets-nodev_all.js.zgz:2162 )
at ZxChatClient._handleError ( Zimlets-nodev_all.js.zgz:9779 )
at ZxChatClient. ( Zimlets-nodev_all.js.zgz:9321 )
at Unknown._g ( Zimlets-nodev_all.js.zgz:3052 )