Messed Docpad installation.
Now Docpad is in /usr/bin/docpad /usr/lib/node_modules
While NPM look at /usr/local/bin/docpad /usr/local/node_modules
Can I specify proper directory for npm where it should look for installed modules?
You probably just need to set the $NODE_PATH environment variable, check out the documentation for more details on loading modules.
Ended up, removing Node.js and npm (installed from docpad scripts).
Installing again node.js and npm from chris-lea/node.js ppa.
Removing docpad by npm from ppa. And then node.js and npm them selfs, and then whole ppa.
Installing node.js and npm from docpad scripts.