Problem uploading file

[Tho Nguyen]

I switch our apache reverse proxy over to nginx and I have a problem.
>From the web browser or the javaclient, I can attach files fine.  But the 
majority of our usage is via a CAD client.  A plugin that hooks in the a CAD 
software like Catia that connects in and checkin/checkout file.  They can 
checkout file fine; just not checking in.

There is nothing in the error log.  Here are some line from the access log when 
it happen.

172.23.65.131 - ifsuser [05/Feb/2008:07:18:57 -0500] 
POST /Filemgr/CheckInServlet?
token=14475C3491031FEAAA6A823FC808E8508F17767ED3A78C540741E4235EFADA0ED57E099F&v
ault=&filename=.xls&opcode=checkin HTTP/1.1 "411" 181 "-" "Jakarta Commons-
HttpClient/3.0" "-"
172.23.65.131 - ifsuser [05/Feb/2008:07:18:57 -0500] 
POST /Filemgr/CheckInServlet?
token=14475C3491031FEAAA6A823FC808E8508F17767ED3A78C540741E4235EFADA0ED57E099F&v
ault=&filename=.xls&opcode=checkin HTTP/1.1 "411" 181 "-" "Jakarta Commons-
HttpClient/3.0" "-"