[racket-dev] workaround for 5.3.6 require for-label problem?

I'm noticing that with version 5.3.6 of DrRacket, a package install of "rsound" hangs during the evaluation of rsound.scrbl.  My guess is that this could be related to the syntax-check error that I get when opening rsound.scrbl in version 5.3.6.  After some work, I discovered that the problem seems to be the use of require (for-syntax ...), and that in fact this setup:

f.rkt:
#lang racket

(require (for-label "g.rkt"))

g.rkt:
#lang racket


... causes the problem. Specifically, I get the error "+: contract violation expected: number? given: #f argument position: 1st other arguments...: 0" in the check-syntax message area when f.rkt is open.

I'm guessing this is a bug that's been fixed.  In the meantime, though, I'm trying to allow my students to see the package docs for rsound. Questions:

1) Is this in fact a bug that's been fixed?
2) Could this actually related to the doc build hang?
3) Is there a simple workaround?

Many thanks in advance for any help!

Best,

John