I propose to add button to default CKEditor toolbar that allows to see it's version. Button name is
Here is how it looks in CKEditor 3 used in In-Portal 5.2:
Here is how it looks in CKEditor 4 used in In-Portal 5.3:
I think this toolbar button in general won't do much harm to users by exposing version of CKEditor. If you don't agree, then we can add it to the CKEditor toolbar, that is used when debug mode is turned on only.