Version:           4.2.1 (using KDE 4.2.1)
OS:                Linux
Installed from:    Debian testing/unstable Packages

In my case, kpackage runs 'smart' to generate package information:

kpackage(21040) kpPty::breakUpCmd:  kpPty::run CMD=" "/bin/sh -c 'smart info --urls >/tmp/kde-eol/smart.list'" " pty =  kpKProcIO(0x8112fe0)

If opened this file (/tmp/kde-eol/smart.list) - and saw, that all information in it is in my system locale language. For example:

Имя: yarssr
Версия: 0.2.2-4
Приоритет: 0
Группа: net
Размер: 260.0kB
Ссылка: 
Флаги: 
Каналы: sid - main contrib non-free; squeeze - main contrib non-free
Сводка: RSS reader for the notification area
Описание:
 Yet Another RSS Reader is an RSS aggregator and reader that displays its
 results in the GNOME or KDE system tray (notification area). To view the
 contents of the feed just click the menu-item and it will launch in your
 favorite browser.
URLs:
 squeeze - main contrib non-free
    http://ftp.uk.debian.org/debian/pool/main/y/yarssr/yarssr_0.2.2-4_all.deb (23.6kB)
 sid - main contrib non-free
    http://ftp.uk.debian.org/debian/pool/main/y/yarssr/yarssr_0.2.2-4_all.deb (23.6kB)

[10:59 eol:~]$ locale
LANG=ru_UA.UTF-8
LANGUAGE=
LC_CTYPE="ru_UA.UTF-8"
LC_NUMERIC="ru_UA.UTF-8"
LC_TIME="ru_UA.UTF-8"
LC_COLLATE="ru_UA.UTF-8"
LC_MONETARY="ru_UA.UTF-8"
LC_MESSAGES="ru_UA.UTF-8"
LC_PAPER="ru_UA.UTF-8"
LC_NAME="ru_UA.UTF-8"
LC_ADDRESS="ru_UA.UTF-8"
LC_TELEPHONE="ru_UA.UTF-8"
LC_MEASUREMENT="ru_UA.UTF-8"
LC_IDENTIFICATION="ru_UA.UTF-8"
LC_ALL=

Then i checked out last sources of kpackage from svn and saw, that parsing of this file is language-dependent (it will work only with english). 

For this reason, kpackage cannot parse this file and hangs (like in bug #168577). This does kpackage unusable for me. The possible solution is to run smart with modified LANG variable from sources (you use 'env' variable to run all with modified enviroment - simple add 'LANG=C; export LANG; ' to it (it works for me fine).

PS sorry for my bad english - as you can see (from 'locale' output), i'm ukrainian ;)