error npm publish -f

the.log

node-make-asset-pipeline$ npm publish -f .
npm WARN publish Forced publish over [email protected]
npm ERR! Failed to update the data
npm ERR! publish fail Cannot publish over existing version.
npm ERR! publish fail Bump the 'version' field, set the --force flag, or
npm ERR! publish fail     npm unpublish '[email protected]'
npm ERR! publish fail and try again
npm ERR! 
npm ERR! System Darwin 10.8.0
npm ERR! command "node" "/Users/pepe/.nvm/v0.4.7/bin/npm" "publish" "-f" "."
npm ERR! cwd /Users/pepe/Git/os/node-make-asset-pipeline
npm ERR! node -v v0.4.7
npm ERR! npm -v 1.0.106
npm ERR! code EPUBLISHCONFLICT
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /Users/pepe/Git/os/node-make-asset-pipeline/npm-debug.log
npm not ok