Hey everyone!

My colleagues at work and me are wondering, if we're allowed to take the Riesling font for commercial use.
I'm working at an ad agency and one of our clients want's to have a logo created from this font for his night club.
I've already asked google for help, but all I could find was a forum entry saying the font's license "got lost and is
now free to use for everybody... on ones own risk" - so, apparently nobody knows, if it's free for commercial use or not.

Does anyone have an idea about the actual license, or whom to contact about this problem?

Thanks in advance and sorry for my bad english