Version:           Unbekannt (using KDE 3.5.5, Debian Package 4:3.5.5a.dfsg.1-2 (testing/unstable))
Compiler:          Target: i486-linux-gnu
OS:                Linux (i686) release 2.6.17

I received a mail with an attachment that has a long file name. It is encoded like this
...
--------------070202080202080901050109
Content-Type: text/plain;
 name*0="PIN_Brief_box1@xx.xxx.43042443bf021c1e00000000_Konfigkarte.confi";
 name*1="guration.txt"
Content-Transfer-Encoding: 8bit
Content-Disposition: inline;
 filename*0="PIN_Brief_box1@xx.xxx.43042443bf021c1e00000000_Konfigkarte.c";
 filename*1="onfiguration.txt"
...

In KMail the attachment reads "guration.txt". Looks like the first part of the name is ignored.