> It sounds like you're issuing the request from the browser. I'd be
> interested to know the details (if you can provide them from the debug
> console or something) of the request headers. Also it'd be helpful to
> know what version of CouchDB is running on each server (and at the
> time of replication, if you've since upgraded).

I was using Chrome and Firefox browsers to issue those requests with
the same results.
The CouchDB version on the original server is: 1.0.1 on the replicated
one it is 1.1.0.
The database was replicated yesterday, and I have not upgraded since.

I tried it now via curl.
If I request the same document id from the two servers without attachments=true
the result is almost exactly the same (the replicated one only adds a
"digest" field to the attachments section.)

If I request the document with attachments, the results for the
original server are as expected:
{"_id":"110221155249562","_rev":"2-ddaf35a53663fb95160709dc74ad4e8f",...,"_attachments":{"log.wav":{"content_type":"audio/x-wav","revpos":2,"data":"UklGRiSAAABXQVZ...."}}}

For the new one it is quite different with some additional headers and
a different encoding:

--695b0c17ab17db91c79747840eb69037
content-type: application/json

{"_id":"110221155249562","_rev":"2-ddaf35a53663fb95160709dc74ad4e8f",...,"_attachments":{"log.wav":{"content_type":"audio/x-wav","revpos":2,"digest":"md5-bMqMA4X3anyOl2M89lifrQ==","length":32812,"follows":true}}}
--695b0c17ab17db91c79747840eb69037

RIFF$200^@^@WAVEfmt ^P^@^@^@^A^@^A^@200>^@^@^@}^@^@^...

It seems to me that the wave file is not put in the json structure but
transferred separately.

Thanks
Matt