mod_scgi and "Expect: 100-continue" headers

What is the best way to deal with "Expect: 100-continue" request  
headers?

Because the scgi protocol expects a body whose length is specified by
the CONTENT_LENGTH value, it seems like "Expect: 100-continue" headers
should be recognized in Apache+mod_scgi and the "100 (continue)"  
intermediate
response should be sent *before* the request is written out to the
scgi-application server.

At present, it seems that the best thing the application can do is
detect the expectation before attempting to read the body, and return
a "417 (Expectation Failed)" response.

Does anyone know a better way to deal with this?