ploticus-doc - what am I doing wrong?

[Andrew Schulman]

I just uploaded a new ploticus package.  It includes subpackages libploticus,
ploticus-common, and ploticus-doc, which are empty obsoleting packages.  The
upload directory structure is

/x86/release/ploticus
/x86/release/ploticus/libploticus
/x86/release/ploticus/ploticus-common
/x86/release/ploticus/ploticus-doc
/x86_64/release/ploticus
/x86_64/release/ploticus/libploticus
/x86_64/release/ploticus/ploticus-common
/x86_64/release/ploticus/ploticus-doc

Upset says:

upset: Error.  Parsing failed. - duplicate packages "ploticus-doc" detected - 
x86/release/ploticus-doc vs.
/var/ftp/pub/cygwin/x86/release/ploticus/ploticus-doc

Am I doing something wrong?  Or is this a one-time error that's been resolved?

Thanks,
Andrew