gistfile1.txt

#######################################

$ cat composer.json 
{
    "require": {
        "npm-asset/grunt-modernizr": "0.5.2"
    }
}

$ composer install
Loading composer repositories with package information
Installing dependencies (including require-dev)
Your GitHub credentials are required to fetch private repository metadata (git://github.com/doctyper/grunt-modernizr.git)
The credentials will be swapped for an OAuth token stored in /home/niko/.composer/auth.json, your password will not be stored
To revoke access to this token you can visit https://github.com/settings/applications
Username: nsams
Password: 
An existing OAuth token for Composer is present and will be reused
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - The requested package npm-asset/grunt-modernizr could not be found in any version, there may be a typo in the package name.

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://groups.google.com/d/topic/composer-dev/_g3ASeIFlrc/discussion> for more details.

Read <http://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.



#######################################
$ cat composer.json 
{
    "require": {
        "npm-asset/uglify-js": "2.4.13"
    }
}

$ composer install
Loading composer repositories with package information
Installing dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - npm-asset/uglify-js v2.4.13 requires npm-asset/optimist >=0.3.5,<0.4 -> satisfiable by npm-asset/optimist[0.3.7, 0.3.6, 0.3.5].
    - npm-asset/uglify-js v2.4.13 requires npm-asset/optimist >=0.3.5,<0.4 -> satisfiable by npm-asset/optimist[0.3.7, 0.3.6, 0.3.5].
    - npm-asset/optimist 0.3.5 requires npm-asset/wordwrap >=0.0.2,<0.1 -> no matching package found.
    - npm-asset/optimist 0.3.5 requires npm-asset/wordwrap >=0.0.2,<0.1 -> no matching package found.
    - npm-asset/optimist 0.3.6 requires npm-asset/wordwrap >=0.0.2,<0.1 -> no matching package found.
    - npm-asset/optimist 0.3.6 requires npm-asset/wordwrap >=0.0.2,<0.1 -> no matching package found.
    - npm-asset/optimist 0.3.7 requires npm-asset/wordwrap >=0.0.2,<0.1 -> no matching package found.
    - npm-asset/optimist 0.3.7 requires npm-asset/wordwrap >=0.0.2,<0.1 -> no matching package found.
    - Installation request for npm-asset/uglify-js 2.4.13 -> satisfiable by npm-asset/uglify-js[v2.4.13].

Potential causes:
 - A typo in the package name
 - The package is not available in a stable-enough version according to your minimum-stability setting
   see <https://groups.google.com/d/topic/composer-dev/_g3ASeIFlrc/discussion> for more details.

Read <http://getcomposer.org/doc/articles/troubleshooting.md> for further common problems.

The bug is caused by Composer that it no manages the redirects for the VCS Repositories:
git://github.com/doctyper/grunt-modernizr.git to git://github.com/Modernizr/grunt-modernizr.git

I search an solution directly in Composer.

The second case is solved (see francoispluchino/composer-asset-plugin@a94c862).

Because 'wordwrap' has no tag version, we must indicate the stability (native system of Composer).

$ cat composer.json
{
    "require": {
        "npm-asset/uglify-js": "2.4.13",
        "npm-asset/wordwrap": "0.0.2@dev"
    }
}

$ composer install
Loading composer repositories with package information
Installing dependencies (including require-dev)
  - Installing npm-asset/uglify-to-browserify (1.0.2)
    Downloading: 100%

  - Installing npm-asset/wordwrap (dev-master b026541)
    Cloning b0265414e9fbce0413d5bf26179685786b759d8a

  - Installing npm-asset/optimist (0.3.7)
    Downloading: 100%

  - Installing npm-asset/amdefine (default)
    Downloading: 100%

  - Installing npm-asset/source-map (0.1.39)
    Downloading: 100%

  - Installing npm-asset/async (0.2.10)
    Downloading: 100%

  - Installing npm-asset/uglify-js (v2.4.13)
    Downloading: 100%

Writing lock file
Generating autoload files