root@mail:~# cat /var/log/mail.log.1 | grep list
Jan 21 08:32:27 mail postfix/spawn[314]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 9494: command time limit exceeded
Jan 21 09:01:32 mail postfix/spawn[314]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 13742: command time limit exceeded
Jan 21 10:56:22 mail postfix/spawn[22788]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 25603: command time limit exceeded
Jan 21 11:37:25 mail postfix/spawn[10793]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 11638: command time limit exceeded
Jan 21 12:05:49 mail postfix/spawn[10793]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 21205: command time limit exceeded
Jan 21 12:37:54 mail postfix/spawn[10793]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 1639: command time limit exceeded
Jan 21 13:27:40 mail postfix/spawn[13933]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 13934: command time limit exceeded
Jan 21 13:35:52 mail postfix/spawn[14254]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 16481: command time limit exceeded
Jan 21 13:54:09 mail postfix/spawn[14254]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 26787: command time limit exceeded
Jan 21 13:55:01 mail postfix/spawn[13933]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 27087: command time limit exceeded
Jan 21 14:17:45 mail postfix/spawn[1602]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 1603: command time limit exceeded
Jan 21 14:21:41 mail postfix/spawn[1126]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 2725: command time limit exceeded
Jan 21 15:06:57 mail postfix/spawn[21888]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 21889: command time limit exceeded
Jan 21 15:24:26 mail postfix/spawn[21888]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 27149: command time limit exceeded
Jan 22 08:12:44 mail postfix/spawn[7741]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 7742: command time limit exceeded
Jan 22 08:29:47 mail postfix/spawn[7741]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 13516: command time limit exceeded
Jan 22 08:52:46 mail postfix/spawn[14771]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 16632: command time limit exceeded
Jan 22 08:55:48 mail postfix/spawn[15828]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 17095: command time limit exceeded
Jan 22 09:09:43 mail postfix/spawn[14771]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 19338: command time limit exceeded
Jan 22 09:12:36 mail postfix/spawn[15828]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 19732: command time limit exceeded
Jan 22 09:43:43 mail postfix/spawn[15828]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 27632: command time limit exceeded
Jan 22 09:52:49 mail postfix/spawn[14771]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 28873: command time limit exceeded
Jan 22 10:46:06 mail postfix/spawn[7039]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 7040: command time limit exceeded
Jan 22 10:54:42 mail postfix/spawn[8275]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 8276: command time limit exceeded
Jan 22 11:02:59 mail postfix/spawn[8638]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 9514: command time limit exceeded
Jan 22 11:11:38 mail postfix/spawn[8275]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 10655: command time limit exceeded
Jan 22 11:16:17 mail postfix/spawn[11122]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 11123: command time limit exceeded
Jan 22 17:04:01 mail postfix/spawn[12501]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 12502: command time limit exceeded
Jan 23 09:50:56 mail postfix/spawn[14136]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 22207: command time limit exceeded
Jan 23 10:59:24 mail postfix/spawn[4134]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 4135: command time limit exceeded
Jan 23 11:17:40 mail postfix/spawn[6141]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 6608: command time limit exceeded
Jan 23 11:40:23 mail postfix/spawn[4134]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 12902: command time limit exceeded
Jan 23 11:52:07 mail postfix/spawn[6141]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 14653: command time limit exceeded
Jan 23 13:46:14 mail postfix/spawn[4652]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 4653: command time limit exceeded
Jan 23 14:55:19 mail postfix/spawn[17926]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 18264: command time limit exceeded
Jan 24 11:48:06 mail postfix/spawn[4690]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 10247: command time limit exceeded
Jan 24 14:05:36 mail postfix/spawn[31482]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 2698: command time limit exceeded
Jan 24 16:16:05 mail postfix/spawn[27118]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 27119: command time limit exceeded
Jan 24 16:20:05 mail postfix/spawn[21684]: warning: /usr/share/univention-mail-postfix/listfilter.py: process id 27737: command time limit exceeded
I think you have to provide some more details.