[galaxy-dev] No action for /admin_toolshed/prepare_for_install

I am trying to install a tool (tmap_wrapper) from the Galaxy toolshed using the Admin interface to Galaxy. Unfortunately, each time I do this I get an error page with the message: No action for /admin_toolshed/prepare_for_install My Galaxy installation is galaxy-dist, revision 7148:17d57db9a7c0. Does anyone know why this might be happening? Thanks, Peter