[racket] ssl-listener not an evt?

Hello,

I'm embarking on an SSL server, using a 'sync' loop to handle
my ports.

However, 'sync' requires evt?... as its arguments, and my SSL listener
ports do not conform to the evt? contract.

See the snippet below:
-------------------------------------------------------------
Welcome to Racket v5.0.2.
 > (require openssl)
 > ssl-available?
#t
 > (define s (ssl-listen 12355))
 > (ssl-listener? s)
#t
 > (evt? s)
#f
 > (sync s)
sync: expects argument of type <evt>; given #<ssl-listener>

  === context ===
/usr/local/lib/racket/collects/racket/private/misc.rkt:74:7

-------------------------------------------------------------
[Racket is build from (UNIX) source on Linux and Solaris, with minimal
  configure flags (i.e. only --prefix)]

The documentation says that an ssl-listener? can be used with sync.

Am I missing something?
Is this a bug?
Is there any way to coerce racket into accepting an ssl-listener? to be
and evt? ?
Can you ever put too many question marks in one email?

Regards,

Tim

-- 
Tim Brown <tim.brown at cityc.co.uk>  | City Computing Limited            |
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