I face an issue when installing a fresh instance of Hubot. The NPM debug log can be found here.
I run NPM in a virtual machine managed by Vagrant, via VirtualBox. Host operating system is Windows. Details about the VM are the following:
Linux precise32 3.2.0-23-generic-pae #36-Ubuntu SMP Tue Apr 10 22:19:09 UTC 2012 i686 i686 i386 GNU/Linux
@francescomari are you still having this problem? I was able to install both of hubot and hubot-scripts without error.
Any idea where this ../coffee-script/bin/coffee comes from? Anyway, looks a lot like a package configuration issue with hubot or hubot-scripts rather than a problem with npm itself.
I have to try again, I will post more details in the following days. Sorry for the late answer.
Everything work as expected now, I'm closing the issue.