System Backup Contains Old E-mail Data

Hi all,
I’m currently running on ROS 6.48.5 LTS. Just out of curiosity i opened my last backup file created with

/system backup

and i noticed that there are still old e-mail accounts/passwords from

/tool email

contained in that file. Thos e-mail settings are not used anymore and should have been overriden. Does anybody know why it’s still there? Via Winbox and also via

/tool email print

i cannot see those old e-mail settings. Is that a bug or is this intended? Most importantly, how do I get red of the old e-mail config leaking into my backup? That boils down to: how can i completely remove old email settings?
Thanks for your hints!
Cheers!

Maybe you will find the answer here http://forum.mikrotik.com/t/system-backup-containing-previous-version-of-edited-scripts/139015/1

Thank you! I will continue asking my questions on that thread. This one can be closed.