No data in params for HTTPS POST request under Apache


I'm trying to submit a form to an Apache web server using a post
request. Under https it works fine. But when using HTTPS there is
nothing in params. Going through the code I find here:

content =['CONTENT_LENGTH'].to_i) || ''

<ck-1.12.5/lib/action_controller/cgi_ext/raw_post_data_fix.rb 54,60

that content is '' even though CONTENT_LENGTH is 106 and there appears
to be a message body.

I've tried submitting the data as url form encoded and yaml encoded
with the appropriate content type headers set to no avail.

Some other people appear to be experiencing this error:

Is this a bug or configuration issue?