Using the squirrelmail setup script conf.pl I tried to
setup default folders with German umlauts in the name,
eg. Entwürfe. This was created incorrectly using the
character set of my file system (which was utf8 in this
case). This is contrary to the imap rfc (rfc 2060
Section 5.1.3), which states that a modified utf7
character set (utf7-imap) should be used.
In this case, the folder should be named "Entw&APw-rfe".
Squirrelmail itself creates the folders correctly, it
is just the setup script that has a problem.