nnimap: How do I work with the "folders" on the IMAP server?

[N. Jackson]

I seem to be making quite good progress with getting my Gnus set up to
do email as well as news. However, one place I am still stuck is
manipulating folders on the IMAP server.

I can create a folder, but only indirectly, by copying or moving an
article to the corresponding Gnus group from the *Summary* or *Article*
buffer, using B c and B m. Is there a direct way to create one?

I can delete a folder using DEL in the *Gnus Browse Server*
buffer. (This appears to fail because it results in a "Wrong type
argument: symbolp" error message, and the buffer doesn't refresh itself,
but the deletion does actually "take" as one can see by reopening the
*Gnus Browse Server* buffer.)

I cannot see how to rename a folder.

I cannot see how to move a folder (and the folders it "contains") "into"
another folder.

Can anyone provide any pointers on how to do these operations?

Thanks,
N.