[qmtest] derivation issues?

[eichin at metacarta.com]

>     arguments = [TextField(name = "script", computed = 1)]

FYI, since IsProperty says
        return self.GetProperty(property_name, "false") == "true"
this needs to be literally "true", ie.
        arguments = [TextField(name = "script", computed = "true")]

(could argue that that should be more liberal, but not very strongly.