#18 apache shows error - can't display graphs

[Anonymous]

I installed nagiostat on my Linux Box and wanted to
display graphs of the ping to a host. I use the
predifined PlotTemplate "ping_pktloss" and added my
host. Nagios is also configured right.

rrdtool creates the archive-file so far, but the
cgi-programm or apache (I don't know so far) can't
show/create a graph.

Here is what I get from apache error log file (arror_log):

ERROR: bad format for [G]PRINT in 'Pktloss MAX: %.4lg%%'

I have not much experience in perl so please help me.

Thanks.