A user is sending a message to a room, trying to change the subject of a room, where he not is authorized to perform this action.
The server responds with a error in line with the message as specified in XEP-0045, Example 87:
<subject>Fire Burn and Cauldron Bubble!</subject>
<error email@example.com' type='auth'>
The SubjectListener still picks this message up as being a Subject change, while the filter lacks a filter on Error.
I fixed this locally by the following fix: