"Error: Cannot find module" after `david update -g jitsu`

Got an error when trying to update globally installed jitsu module via david
- Node: **0.10.12**
- OSX: **10.8.4**
- david: **1.9.0**

``` shell
$ david update -g jitsu
npm http ...
..snip...
```

Stack trace:

``` shell
/usr/local/lib/node_modules/david/node_modules/npm/node_modules/lockfile/lockfile.js:46
throw er
^
Error: Cannot find module '/usr/local/lib/node_modules/david/node_modules/npm/lib/build.js'
at Function.Module._resolveFilename (module.js:338:15)
at Function.Module._load (module.js:280:25)
at Module.require (module.js:364:17)
at require (module.js:380:17)
at Object.defineProperty.get (/usr/local/lib/node_modules/david/node_modules/npm/lib/npm.js:185:15)
at /usr/local/lib/node_modules/david/node_modules/npm/lib/install.js:1053:18
at asyncMap (/usr/local/lib/node_modules/david/node_modules/npm/node_modules/slide/lib/async-map.js:27:18)
at /usr/local/lib/node_modules/david/node_modules/npm/lib/install.js:587:7
at asyncMap (/usr/local/lib/node_modules/david/node_modules/npm/node_modules/slide/lib/async-map.js:27:18)
at /usr/local/lib/node_modules/david/node_modules/npm/lib/install.js:568:5
```

Of interest, I now realise now that `david update` doesn't target individual modules, so adding jitsu to the command did nothing, and david tried to update all the things. Not a problem, just worth noting.

Also, for debugging, I ran a `david -g` before hand, and david was one of the global modules that was due for updating...

``` shell
$ david -g
npm http ...snip...

Outdated Global Dependencies

generator-karma (package: 0.4.1, latest: 0.5.0)
generator-angular (package: 0.3.1, latest: 0.4.0)
yo (package: 1.0.0-rc.1.4, latest: 1.0.3)
david (package: 1.9.0, latest: 2.0.0)
bower (package: 1.1.0, latest: 1.2.4)
npm (package: 1.2.32, latest: 1.3.9)
browserify (package: 2.26.0, latest: 2.29.0)

npm install --global generator-karma@0.5.0 generator-angular@0.4.0 yo@1.0.3 david@2.0.0 bower@1.2.4 npm@1.3.9 browserify@2.29.0
```