Hoary to Breezy upgrade problem

[Astrit Zhushi]

Greetings to the list,


On one of machines I had installed Ubuntu 5.04 Hoary and wanted to 
upgrade to Breezy 5.10. I have edited /etc/apt/sources.list and ran 
apt-get update followed by dist-upgrade. However, when coming to postfix 
upgrade the system just reboots:


Preconfiguring packages ...
(Reading database ... 13796 files and directories currently installed.)
Preparing to replace postfix 2.1.5-9ubuntu3 (using 
.../postfix_2.2.4-1ubuntu2_i386.deb) ...
Unpacking replacement postfix ...

After this point system just reboots. I have tried several times but my 
system always reboots. Furthermore, I tried to remove postfix package 
but I can't do, dpkg complains that the package is in half installed 
stae and can't be removed.


Best regards,
Astrit Zhushi