But in logs, that I send you, and in some tables in database I can find some vlan numbers... Your suggestion is to use these guide lines: http://metanav.ntnu.no/moin.cgi/SubnetsAndVlans ?
We try to find VLAN numbers on a best-effort basis, and for most devices this works. Where it doesn't, you can specify it manually in the interface descrption: see "Guide lines for configuring router interface descriptions"
Are you able to look at the output written to the console by the applet? There it writes the URL it uses to fetch data from the server; if you could paste that link into a browser and provide the output it would be very helpful in debugging this issue.
In which log I can find this?
You need to look at the Java console. On Windows you can find this by right-clicking the Java tray icon.
-- Kristian