Webugi: Status: Traffic Graph

[ugur]

i use : 2.0.3-RELEASE (amd64)

Status: Traffic Graph, any interface,  not show any graph, this error:

This page contains the following errors:

error on line 1 at column 40: Unsupported encoding iso-8859-1
Below is a rendering of the page up to the first error.

note: browser is chromium. same machine, if browser firefox, no error.