Error when trying to install titanium-backbone

titanium-backbone_error

npm ERR! git clone git@github.com:trabian/stitch.git Cloning into '/tmp/npm-1338221487054/1338221492364-0.7780230774078518'...
npm ERR! git clone git@github.com:trabian/stitch.git 
npm ERR! git clone git@github.com:trabian/stitch.git Permission denied (publickey).
npm ERR! git clone git@github.com:trabian/stitch.git fatal: The remote end hung up unexpectedly

npm ERR! Error: `git "clone" "git@github.com:trabian/stitch.git" "/tmp/npm-1338221487054/1338221492364-0.7780230774078518"` failed with 128
npm ERR!     at ChildProcess.<anonymous> (/usr/local/lib/node_modules/npm/lib/utils/exec.js:58:20)
npm ERR!     at ChildProcess.emit (events.js:70:17)
npm ERR!     at maybeExit (child_process.js:362:16)
npm ERR!     at Process.onexit (child_process.js:398:5)
npm ERR! You may report this log at:
npm ERR!     <http://github.com/isaacs/npm/issues>
npm ERR! or email it to:
npm ERR!     <npm-@googlegroups.com>
npm ERR! 
npm ERR! System Darwin 11.4.0
npm ERR! command "node" "/usr/local/bin/npm" "install" "titanium-backbone" "-g"
npm ERR! cwd /Volumes/Stuff/Projects/titanium/titanium-backbone
npm ERR! node -v v0.6.18
npm ERR! npm -v 1.1.21
npm ERR! message `git "clone" "git@github.com:trabian/stitch.git" "/tmp/npm-1338221487054/1338221492364-0.7780230774078518"` failed with 128
npm ERR! 
npm ERR! Additional logging details can be found in:
npm ERR!     /Volumes/Stuff/Projects/titanium/titanium-backbone/npm-debug.log