devsw_detach is failing -- is this a manifestation of PR kern/56962?

[Brian Buhrow]

        Hello.  I've found that after I perform a modunload on the module I'm 
working on, I cannot
then modload the module because devsw_attach fails to attach the same module 
again.  And, yes,
the module calls devsw_detach before it unloads.

        
        I'm runing NetBSD-9.99.77, which predates the pr kern/56962 fixes.  Is 
this behavior
expected prior to the fix for this bug or am I running into something else?

-thanks
-Brian