Java error on combination chart preview

[luqasshh]

Hello,
currently I am developing a report on which I have a requirement to display a combination chart. Unfortunately when I place a chart on my report and try to add any of series I get java error (see the screenshot attached). Seems like it's related only to chart preview because when running the report the chart presents correct values. This error is displayed anytime i modify the chart or any of its properties. Has anyone ever encountered this kind of error? I tried googling it, no luck.

I'm running Report Studio in Cognos Express 10.2.1 installation with fix pack 3 also installed. Thanks in advance for any response.

Regards