IMAP Folder Mail Separator

Hi,

I have a fedora21 install with dovecot-2.2.18, and when creating a new subfolder with thunderbird, the actual folder name is "Folder1^Folder2" with a carat as a separator, instead of creating Folder2 in the Folder1 directory.

Is this a thunderbird problem? I don't recall having this problem prior to upgrading to fedora21, so thought maybe it's a dovecot problem.

Maybe the separator character is customizable?

Thanks, Alex