help! how to replace the default picure?

@mailovee (265)
China
April 13, 2007 11:58pm CST
the picture thats how up everytime you reply to or start a discussion in the top left corner. and whats the picture called,my english is poor,hope you can understand me,thanks a lot
1 response
prashantrjp
@prashantrjp (275)
• India
15 Apr 07
donno how u got in first place