/usr/share/roundcube/plugins/sieverules/ is in roundcube-plugins-extra 0.6-20111030.
This file is owned by root:root, with mode 0o755.
..
/usr/share/roundcube/plugins/sieverules/config.inc.php
/usr/share/roundcube/plugins/sieverules/config.inc.php.dist
/usr/share/roundcube/plugins/sieverules/importFilters/
/usr/share/roundcube/plugins/sieverules/importFilters/avelsieve.php
/usr/share/roundcube/plugins/sieverules/importFilters/ingo.php
/usr/share/roundcube/plugins/sieverules/include/
/usr/share/roundcube/plugins/sieverules/include/rcube_sieve.php
/usr/share/roundcube/plugins/sieverules/include/rcube_sieve_script.php
/usr/share/roundcube/plugins/sieverules/jquery.maskedinput.js
/usr/share/roundcube/plugins/sieverules/lib/
/usr/share/roundcube/plugins/sieverules/lib/Net/
/usr/share/roundcube/plugins/sieverules/lib/Net/Sieve.php
/usr/share/roundcube/plugins/sieverules/localization/
/usr/share/roundcube/plugins/sieverules/localization/ca_ES.inc
/usr/share/roundcube/plugins/sieverules/localization/cs_CZ.inc
/usr/share/roundcube/plugins/sieverules/localization/de_CH.inc
/usr/share/roundcube/plugins/sieverules/localization/de_DE.inc
/usr/share/roundcube/plugins/sieverules/localization/en_GB.inc
/usr/share/roundcube/plugins/sieverules/localization/en_US.inc
/usr/share/roundcube/plugins/sieverules/localization/es_AR.inc
/usr/share/roundcube/plugins/sieverules/localization/es_ES.inc
/usr/share/roundcube/plugins/sieverules/localization/et_EE.inc
/usr/share/roundcube/plugins/sieverules/localization/fr_FR.inc
/usr/share/roundcube/plugins/sieverules/localization/hu_HU.inc
/usr/share/roundcube/plugins/sieverules/localization/it_IT.inc
/usr/share/roundcube/plugins/sieverules/localization/nl_NL.inc
/usr/share/roundcube/plugins/sieverules/localization/pl_PL.inc
/usr/share/roundcube/plugins/sieverules/localization/pt_BR.inc
/usr/share/roundcube/plugins/sieverules/localization/pt_PT.inc
/usr/share/roundcube/plugins/sieverules/localization/ro_RO.inc
/usr/share/roundcube/plugins/sieverules/localization/ru_RU.inc
/usr/share/roundcube/plugins/sieverules/localization/sk_SK.inc
/usr/share/roundcube/plugins/sieverules/localization/sl_SI.inc
/usr/share/roundcube/plugins/sieverules/localization/sv_SE.inc
/usr/share/roundcube/plugins/sieverules/sieverules.js
/usr/share/roundcube/plugins/sieverules/sieverules.php
/usr/share/roundcube/plugins/sieverules/skins/
/usr/share/roundcube/plugins/sieverules/skins/default/
/usr/share/roundcube/plugins/sieverules/skins/default/help.gif
/usr/share/roundcube/plugins/sieverules/skins/default/icons.gif
/usr/share/roundcube/plugins/sieverules/skins/default/icons.png
/usr/share/roundcube/plugins/sieverules/skins/default/ie6hacks.css
/usr/share/roundcube/plugins/sieverules/skins/default/iehacks.css
/usr/share/roundcube/plugins/sieverules/skins/default/safari.css
/usr/share/roundcube/plugins/sieverules/skins/default/sieverules.css
/usr/share/roundcube/plugins/sieverules/skins/default/templates/
/usr/share/roundcube/plugins/sieverules/skins/default/templates/advancededitor.html
/usr/share/roundcube/plugins/sieverules/skins/default/templates/editsieverule.html
/usr/share/roundcube/plugins/sieverules/skins/default/templates/setupsieverules.html
/usr/share/roundcube/plugins/sieverules/skins/default/templates/sieverules.html