One thing that might work is replacing, in function "empathy_misc_get_pixbuf_for_notification" , the call for "empathy_pixbuf_from_icon_name_sized (icon_name, size)" by a call for "pixbuf_avatar = empathy_pixbuf_from_icon_name_sized ("stock_person", size)".
One thing that might work is replacing, in function "empathy_ misc_get_ pixbuf_ for_notificatio n" , the call for "empathy_ pixbuf_ from_icon_ name_sized (icon_name, size)" by a call for "pixbuf_avatar = empathy_ pixbuf_ from_icon_ name_sized ("stock_person", size)".