crystal report paper size

Hi,
I've a problem. I have to set the paper size of a report (crystal report) at
runtime, but the size I need to set isn't in the list of
CrystalDecisions.Shared.PaperSize.

I want do something like this:
myreport.PrintOptions.PaperSize = new CrystalDecisions.Shared.PaperSize
(width, height)

There is a way to do that?

Thank you
Chiara

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