Here's a more detailed explanation:
Bug in PictureVal rendering
http://weblogs.foxite.com/cesarchalom/archive/2007/04/10/3669.aspx

>Hi Cesar.
>
>Yes, I'm working on a new Outlook2003Bar version and PictureVal could save me some time and eliminate the needs to send the physical images or create them with GDI+.
>
>For now, I'll follow your suggestion. Let's see what MS says about fix this bug.
>
>Tks a lot brother!