The ?iso-8859-1?B? - Encoding/Decoding Command is
not supported.
For example, if you write an eMail in a german Outlook
2000 SR-1 with the subject "töst = töst" you will find the
following line in the mail-header:
Subject: =?iso-8859-1?B?dPZzdCA9IHT2c3Q=?=
The line is Base64 - Encoded.