Nginx rejects Content-Type without a space before "boundary".

I ran into this bug when testing an app on both iOS and Android and using Nginx as a reverse proxy to my application server. The Content-Type produced by the iOS backend is accepted just fine (with the space), but the Content-Type produced by the Android backend is rejected by Nginx as being a malformed HTTP request (a 400). See more discussion here:
http://stackoverflow.com/questions/17990705/phonegap-uploading-file-to-server-using-multipart-form-data