[racket] bitmap% and OpenGL. Maybe bug?

Dear All, I am using Racket 5.1 on Windows.I have a program which renders an OpenGL image into a bitmap. The following used to work inPLT-Scheme. (define a (make-object bitmap% 100 100 #f))
(define b (new bitmap-dc% (bitmap a)))
(send b get-gl-context) Now it returns #f.Is it a bug or feature?Is there any way that I can make it work again easily? Thanks, Peter Ivanyi
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