[Displays icons in message window showing whether your last outgoing message was read / is still unread.]
[Last message read at %X %x]
[Last message read]
[Last message is not read]
[Last message was not sent]
[MessageState unread extra icon]
[Unread message icon]
[Read message icon]
[Failed sending icon]
[Sending message icon]
[Unread clist extra icon]