[Users] rename mailbox (toplevel folder)

[Michael]

This is probably a faq ... or maybe not ? Just, for some reasons i want to rename the top level 'mailbox' folder. There are lots of subfolders and a huge mass of configured filters, and i like to know how to preserve especially the filter.

Would i have to 'add' the renamed folder as new mailbox (and rebuild the folder tree) ? 
Wouldn't the filters naturally be 'lost' and at least i'd have to fiddle with sed -i ...?

tia for hints

Micha