We monitor a log with logrt:
logrt["/var/log/zabbix/rsyslog2zabbix.log(|[1-4])",,,100]
zabbix has read access on this file and get records without any problem.

But when we edit the log with root, we get this strange error in zabbix server logfile (it is normal that zabbix can't read the file because of access permissions but it is strange it follows the swap file):
12403:20120917:173106.415 cannot open '/var/log/zabbix/.rsyslog2zabbix.log.swp': [13] Permission denied
12403:20120917:173106.415 cannot close file '/var/log/zabbix/.rsyslog2zabbix.log.swp': [9] Bad file descriptor
12403:20120917:173106.415 Active check [logrt["/var/log/zabbix/rsyslog2zabbix.log(|[1-4])",,,100]] is not supported. Disabled.

If we look at inodes, they are different:
ls -li .rsyslog2zabbix.log.swp
90 rw------ 1 root root 16384 Sep 18 15:01 .rsyslog2zabbix.log.swp
ls -li rsyslog2zabbix.log
83 rw------ 1 zabbix zabbix 230374 Sep 18 15:01 rsyslog2zabbix.log

We confess we were not able to reproduce this problem on a Debian Squeeze server.
Thanks for help