This is my composer.json
"require": {
    "php": ">=5.3.3",
    "symfony/symfony": "2.4.1",
    "doctrine/orm": "2.4.1",
    "doctrine/doctrine-bundle": "1.2.0",
    "twig/extensions": "1.0.1",
    "symfony/assetic-bundle": "2.3.0",
    "symfony/dom-crawler": "2.3.10",
    "symfony/swiftmailer-bundle": "2.3.4",
    "symfony/monolog-bundle": "2.4.1",
    "sensio/distribution-bundle": "2.3.4",
    "sensio/framework-extra-bundle": "3.0",
    "sensio/generator-bundle": "2.3.4",
    "incenteev/composer-parameter-handler": "2.1.0",
    "tobie/ua-parser": "dev-master"
},
{
    ...
},
"config": {
    "bin-dir": "bin"
},
"minimum-stability": "dev",
"extra": {
    "symfony-app-dir": "app",
    "symfony-web-dir": "web",
    "incenteev-parameters": {
        "file": "app/config/parameters.yml"
    },
    "branch-alias": {
        "dev-master": "2.4-dev"
    }
}
However, when i run composer install, it is throwing the following errors:
Your requirements could not be resolved to an installable set of packages.
Problem 1 - Installation request for symfony/framework-standard-edition 2.4.x-dev -> s atisfiable by symfony/framework-standard-edition[2.4.x-dev]. - symfony/framework-standard-edition 2.4.x-dev requires tobie/ua-parser dev- master -> no matching package found.
Potential causes: - A typo in the package name - The package is not available in a stable-enough version according to your min imum-stability setting see https://groups.google.com/d/topic/composer-dev/_g3ASeIFlrc/discussion f or more details.
Read http://getcomposer.org/doc/articles/troubleshooting.md for further common problems.