How to add my own post/page Status?

Hi all!

I have this one question that is important to my current 2 weeks deadline project… How to add custom post/page status that is visible in Edit panel and how to handle that status once when post got it?

And please, no custom_fields related solutions. It is too complicated to my client ??

Hope there is good solution for it. I love WP and I am using it for years (remember that v1.5?)! when I get more free time I plan to support it like you all guyz ??