[collectd] Strange results with tail plugin

[Marcin Rzepecki]

Hello, 
i have problems using tail plugin for collecting stats.

My conf looks like that:
<Plugin tail>
        <File "/var/log/postfix">
                Instance "sshd"
                <Match>
                        Regex "status=sent"
                        DSType "CounterInc"
                        Type "counter"
                        Instance "postfix_sent"
                </Match>
        </File>
</Plugin>

The whole line looks like this for example:
Nov 24 03:03:57 freebsd postfix/local[65536]: 54027425EB: to=<mr at xxxx.xx.xx>, orig_to=<root>, relay=local, delay=0.19,
delays=0.06/0/0/0.13, dsn=2.0.0, status=sent (delivered to command: /usr/local/bin/dspam --deliver=innocent --user $USER)

I see that something is beeing matched, but when i dump rrd file using
rrdtool i can see that some values are very high:
<!-- 2008-11-24 02:21:30 CET / 1227489690 --> <row><v> 5.7142857143e-02 </v></row>
<!-- 2008-11-24 02:22:40 CET / 1227489760 --> <row><v> 0.0000000000e+00 </v></row>
<!-- 2008-11-24 02:23:50 CET / 1227489830 --> <row><v> 6.1356675443e+07 </v></row>
<!-- 2008-11-24 02:25:00 CET / 1227489900 --> <row><v> 0.0000000000e+00 </v></row>
<!-- 2008-11-24 02:28:30 CET / 1227490110 --> <row><v> 2.8571428571e-02 </v></row>
<!-- 2008-11-24 02:29:40 CET / 1227490180 --> <row><v> 0.0000000000e+00 </v></row>
<!-- 2008-11-24 02:30:50 CET / 1227490250 --> <row><v> 6.1356675629e+07 </v></row>

Am I doing something wrong? As i know CounterInc should only increase
value when match is found. 
I've tested with many logfiles  with different regex without success.
I'm using collectd-4.5.1 from port tree on FreeBSD-8.0-Current

Thanks for any help.
Best regards, 

-- 
Marcin Rzepecki