[Netdisco] trouble with 'svg' networkmap

[Николай Г. П. <ra...@di...>]

tOS: freebsd 8.1 Release
Netdisco Version   : 1.0
SNMP::Info Version : 2.01
Net-SNMP Version   : 5.05
Perl Version       : 118.53.46.49.48.46.49
graphviz-2.26.3_3
p5-Graph-0.94,1
p5-GraphViz-2.04_3

'svg' network map graph don't display in opera - "Applet not found", in 
firefox,chrome -clear area, just in the bottom have a comment with 
description. What's a problem?
Why 'svg' graph create:
-rw-rw-rw-  1 www  www  66219  4 фев 12:46 
(..)/apache22/data/netdisco/netmap.svg

,but not displayed?