SSRS 2008 R2 Line Chart Issue

Hi, 

Problem:

I have an issue of SSRS Line Chart extending backward and forward (same issue discussed in post - http://social.msdn.microsoft.com/Forums/en-US/sqlreportingservices/thread/3cebd5b2-bb15-4bd1-be16-0daadc613082/) when Empty point option Value is set Average 

I tried sorting on Category Group as suggested by Sean Boon in the URL mentioned above. But, still the issue is not fixed. 

I am using SSRS R2. 

Thoughts ?