Fileupload doesn't work in Richfaces 4.0.0 Final

Hi,

Richfaces fileupload doesn't work in Spring Web Flow 2.3.0. After selecting a file and pressing the "Upload" button a "Server error" message shows up.
This error message originates from an exception in Richfaces method MultipartRequest.initialize() and states
"org.richfaces.exception.FileUploadException: The request was rejected because no multipart boundary was found".
It seems like MultipartRequest.initialize() is passed twice??? The FileUploadException occurs in the second pass.
Outside Spring Web Flow Richfaces fileupload works fine.

Regards
Gerhard Hofmann