[Mondrian] Help in Chart

[miguel]

Hi,
I was working with Mondrian and I have a question without solution. I
want
to configure the graphic that Mondrian shows, I need that when people
access
to Mondrian they see only the graphic about my "query".  I was looking
into
all Mondrian files, and I found this into web.xml file:

  <servlet>
    <servlet-name>GetChart</servlet-name>
    <display-name>GetChart</display-name>
    <description>Default configuration created for
servlet.</description>
    <servlet-class>com.tonbeller.jpivot.chart.GetChart</servlet-class>
  </servlet>
 
With this I understand that:
1. I need the GetChart servlet, in order to configure the graphic type,
the
values to show it, axis name, etc.  
2. I can find this file into: mondrian/WEB-INF/lib/jpivot.jar
3. I need to modify this file.

Then my questions are:
1. How Can I modify this file? or What file I need to modify?
2. How Can I configure Mondrian graphics in order to it maintain the
values
that I put as a default values?

Thanks in advance and regards,