[collectd] tail plugin problem

[sergio]

Hello,

I want to collect rejected and accepted messages by exim.
So I added "LoadPlugin tail" and wrote this rule:
<Plugin "tail">
	<File "/var/log/exim4/mainlog">
		Instance "exim"
		<Match>
			Regex " Completed$"
			DSType "CounterInc"
			Type "counter"
			Instance "accepted"
		</Match>
		<Match>
			Regex " rejected "
			DSType "CounterInc"
			Type "counter"
			Instance "rejected"
		</Match>
	</File>
</Plugin>
But collection.cgi doesn't show picture.

With rrdtool dump I see, that data stored in rrd. But nothing happens.
I have tryed collectd 4.4.2-3~bpo40+1 from etch-backports with librrd2 
on etch i386 system and collectd 4.5.1-1 (backported from experimental) 
with librrd2 and librrd4 on etch amd64.

When I run:
./collection.cgi 
'?action=show_graph;plugin=tail;type=counter;timespan=hour;plugin_instance=exim;type_instance=rejected;host=host'
I get: Content-Type: image/png.
Whith other plugin I get image on stdout.

I donw know how to use rrdtool graph. This doesn't works for all plugins.
% rrdtool graph qwe.png --end now --start end-600s --width 400 
DEF:value=counter-rejected.rrd:value:AVERAGE
0x0

You can get rrd here:
http://misc.sergio.spb.ru/counter-rejected.rrd

-- 
sergio