[racket] raco pkg install/remove problem

Hi all,

I just installed a package with raco pkg install:

$ raco pkg install
github://github.com/tonyg/racket-pretty-printing-combinators/master

... and then removed it with raco pkg remove:

raco pkg remove racket-pretty-printing-combinators

... only to be told:

Inferred package scope: /home/tonyg/src/racket/racket/share/pkgs
Removing racket-pretty-printing-combinators
raco setup: directory:
#<path:/home/tonyg/src/racket/racket/share/pkgs/racket-pretty-printing-combinators>
does not exist for collection: "racket-pretty-printing-combinators"
  context...:
   /home/tonyg/src/racket/racket/collects/setup/setup-unit.rkt:264:2:
core151
   /home/tonyg/src/racket/racket/collects/setup/setup-unit.rkt:379:4:
for-loop
   /home/tonyg/src/racket/racket/collects/pkg/main.rkt: [running body]
   /home/tonyg/src/racket/racket/collects/pkg/raco.rkt: [traversing imports]
   /home/tonyg/src/racket/racket/collects/raco/raco.rkt: [running body]
   /home/tonyg/src/racket/racket/collects/raco/main.rkt: [running body]

What did I do wrong?

Cheers,
  Tony