alpine deletes email

[pobo]

I got
Alpine 2.10 (DEB 1266 2009-07-14) built Tue May 21 11:14:32 UTC 2013 on akateko

the standard folder for read mails was "read-mail", which I used for a while. Today I decided to rename it to just "read", because i find it easier. I forgot to re-configure the rule for read mails.
After I had read today's emails, on exit, Alpine deleted my email in the Inbox and wanted to write it to the folder "read-mail", which did not exist any more. It asked "folder read-mail doesn't exist. Create it?" and I answered with "no".

What I didn't expect: All those emails are in Nirvana now. They are not in the Inbox anymore, and I can't find them anywhere else. I suggest that Emails, when being moved, should be only deleted after they have been successfully postponed to the other folder.

I am using the following system:
Linux pulmo-ThinkPad-T410s 3.11.0-12-generic #19-Ubuntu SMP Wed Oct 9 16:20:46 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux
No LSB modules are available.
Distributor ID: LinuxMint
Description: Linux Mint 16 Petra
Release: 16
Codename: petra