Kmail hang, easier way to fix?

Hello all:

    I've been using KMail for over a year now, and I've been very happy with it. 
 But lately it's started causing me problems.  Occasionally when I exit the 
application, and then return, and the new one doesn't start.  When I do a "ps 
-a" I find that there's a Kmail process marked "D"; which I understand to 
mean "uniterruptable sleep" or "waiting for I/O." This process is totally 
unkillable, even as root.  Logging out and logging back in (which always 
worked in the past for me when Netscape would hang) doesn't work.  I've 
actually had to reboot the system (Noooo!!  That was why I'm migrating away 
from Windows!)  Strangely enough, the last time I rebooted (just now) my 
inbox and trash folders were mysteriously empty.   Only "sent-mail" was still 
there, which is good, because I've been too lazy to copy peoples' addreses 
into my address book (guess I should do that.)  Anyway, does anyone know of a 
more graceful way to restart Kmail when it hangs?

Thanks,
Vaughn Treude
Nakota Software, Inc.
Custom Software Development
User Interface Design / Automation / Client-Server / Data Acquisition