diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index 0ad433c90..0eed0050a 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -180,7 +180,9 @@ class Installer
                 $updatedLock = $this->locker->setLockData(
                     $this->repositoryManager->getLocalRepository()->getPackages(),
                     $this->devMode ? $this->repositoryManager->getLocalDevRepository()->getPackages() : null,
-                    $aliases
+                    $aliases,
+                    $this->package->getMinimumStability(),
+                    $this->package->getStabilityFlags()
                 );
                 if ($updatedLock) {
                     $this->io->write('<info>Writing lock file</info>');
@@ -202,13 +204,18 @@ class Installer
 
     protected function doInstall($localRepo, $installedRepo, $aliases, $devMode = false)
     {
+        $minimumStability = $this->package->getMinimumStability();
+        $stabilityFlags = $this->package->getStabilityFlags();
+
         // initialize locker to create aliased packages
         if (!$this->update && $this->locker->isLocked($devMode)) {
             $lockedPackages = $this->locker->getLockedPackages($devMode);
+            $minimumStability = $this->locker->getMinimumStability();
+            $stabilityFlags = $this->locker->getStabilityFlags();
         }
 
         // creating repository pool
-        $pool = new Pool($this->package->getMinimumStability(), $this->package->getStabilityFlags());
+        $pool = new Pool($minimumStability, $stabilityFlags);
         $pool->addRepository($installedRepo);
         foreach ($this->repositoryManager->getRepositories() as $repository) {
             $pool->addRepository($repository);
diff --git a/src/Composer/Package/Locker.php b/src/Composer/Package/Locker.php
index 7f6b738f6..d7502bfdb 100644
--- a/src/Composer/Package/Locker.php
+++ b/src/Composer/Package/Locker.php
@@ -82,10 +82,10 @@ class Locker
      */
     public function getLockedPackages($dev = false)
     {
-        $lockList = $this->getLockData();
+        $lockData = $this->getLockData();
         $packages = array();
 
-        $lockedPackages = $dev ? $lockList['packages-dev'] : $lockList['packages'];
+        $lockedPackages = $dev ? $lockData['packages-dev'] : $lockData['packages'];
         $repo = $dev ? $this->repositoryManager->getLocalDevRepository() : $this->repositoryManager->getLocalRepository();
 
         foreach ($lockedPackages as $info) {
@@ -128,22 +128,38 @@ class Locker
         return $packages;
     }
 
+    public function getMinimumStability()
+    {
+        $lockData = $this->getLockData();
+
+        // TODO BC change dev to stable end of june?
+        return isset($lockData['minimum-stability']) ? $lockData['minimum-stability'] : 'dev';
+    }
+
+    public function getStabilityFlags()
+    {
+        $lockData = $this->getLockData();
+
+        return isset($lockData['stability-flags']) ? $lockData['stability-flags'] : array();
+    }
+
     public function getAliases()
     {
-        $lockList = $this->getLockData();
-        return isset($lockList['aliases']) ? $lockList['aliases'] : array();
+        $lockData = $this->getLockData();
+
+        return isset($lockData['aliases']) ? $lockData['aliases'] : array();
     }
 
     public function getLockData()
     {
-        if (!$this->lockFile->exists()) {
-            throw new \LogicException('No lockfile found. Unable to read locked packages');
-        }
-
         if (null !== $this->lockDataCache) {
             return $this->lockDataCache;
         }
 
+        if (!$this->lockFile->exists()) {
+            throw new \LogicException('No lockfile found. Unable to read locked packages');
+        }
+
         return $this->lockDataCache = $this->lockFile->read();
     }
 
@@ -156,13 +172,15 @@ class Locker
      *
      * @return Boolean
      */
-    public function setLockData(array $packages, $devPackages, array $aliases)
+    public function setLockData(array $packages, $devPackages, array $aliases, $minimumStability, array $stabilityFlags)
     {
         $lock = array(
             'hash' => $this->hash,
             'packages' => null,
             'packages-dev' => null,
             'aliases' => $aliases,
+            'minimum-stability' => $minimumStability,
+            'stability-flags' => $stabilityFlags,
         );
 
         $lock['packages'] = $this->lockPackages($packages);
diff --git a/tests/Composer/Test/Package/LockerTest.php b/tests/Composer/Test/Package/LockerTest.php
index 729da4b93..a67beb277 100644
--- a/tests/Composer/Test/Package/LockerTest.php
+++ b/tests/Composer/Test/Package/LockerTest.php
@@ -157,9 +157,11 @@ class LockerTest extends \PHPUnit_Framework_TestCase
                 ),
                 'packages-dev' => array(),
                 'aliases' => array(),
+                'minimum-stability' => 'dev',
+                'stability-flags' => array(),
             ));
 
-        $locker->setLockData(array($package1, $package2), array(), array());
+        $locker->setLockData(array($package1, $package2), array(), array(), 'dev', array());
     }
 
     public function testLockBadPackages()
@@ -177,7 +179,7 @@ class LockerTest extends \PHPUnit_Framework_TestCase
 
         $this->setExpectedException('LogicException');
 
-        $locker->setLockData(array($package1), array(), array());
+        $locker->setLockData(array($package1), array(), array(), 'dev', array());
     }
 
     public function testIsFresh()