diff --git a/src/Composer/DependencyResolver/PoolBuilder.php b/src/Composer/DependencyResolver/PoolBuilder.php
index f9a7541c3..5376367e2 100644
--- a/src/Composer/DependencyResolver/PoolBuilder.php
+++ b/src/Composer/DependencyResolver/PoolBuilder.php
@@ -62,8 +62,12 @@ class PoolBuilder
         foreach ($request->getJobs() as $job) {
             switch ($job['cmd']) {
                 case 'install':
-                    $loadNames[$job['packageName']] = $job['constraint'];
-                    $this->nameConstraints[$job['packageName']] = $job['constraint'] ? new MultiConstraint(array($job['constraint']), false) : null;
+                    // TODO currently lock above is always NULL if we adjust that, this needs to merge constraints
+                    // TODO does it really make sense that we can have install requests for the same package that is actively locked with non-matching constraints?
+                    // also see the solver-problems.test test case
+                    $constraint = array_key_exists($job['packageName'], $loadNames) ? null : $job['constraint'];
+                    $loadNames[$job['packageName']] = $constraint;
+                    $this->nameConstraints[$job['packageName']] = $constraint ? new MultiConstraint(array($job['constraint']), false) : null;
                     break;
             }
         }
@@ -199,6 +203,7 @@ class PoolBuilder
                     // TODO addConstraint function?
                     $this->nameConstraints[$require] = new MultiConstraint(array_merge(array($linkConstraint), $this->nameConstraints[$require]->getConstraints()), false);
                 }
+                // else it is null and should stay null
             } else {
                 $this->nameConstraints[$require] = null;
             }
diff --git a/src/Composer/DependencyResolver/Problem.php b/src/Composer/DependencyResolver/Problem.php
index 2c1c7236a..bc3f2de04 100644
--- a/src/Composer/DependencyResolver/Problem.php
+++ b/src/Composer/DependencyResolver/Problem.php
@@ -211,10 +211,10 @@ class Problem
             case 'fix':
                 $package = $job['package'];
                 if ($job['lockable']) {
-                    return 'Package '.$package->getPrettyName().' is locked to version '.$package->getPrettyVersion();
-                } else {
-                    return 'Package '.$package->getPrettyName().' is present at version '.$package->getPrettyVersion() . ' and cannot be modified by Composer';
+                    return $package->getPrettyName().' is locked to version '.$package->getPrettyVersion().' and an update of this package was not requested.';
                 }
+
+                return $package->getPrettyName().' is present at version '.$package->getPrettyVersion() . ' and cannot be modified by Composer';
             case 'install':
                 $packages = $this->pool->whatProvides($packageName, $constraint);
                 if (!$packages) {
diff --git a/src/Composer/DependencyResolver/RuleSetGenerator.php b/src/Composer/DependencyResolver/RuleSetGenerator.php
index 0c7350cdd..d42617a7a 100644
--- a/src/Composer/DependencyResolver/RuleSetGenerator.php
+++ b/src/Composer/DependencyResolver/RuleSetGenerator.php
@@ -261,6 +261,10 @@ class RuleSetGenerator
         $unlockableMap = $request->getUnlockableMap();
 
         foreach ($request->getFixedPackages() as $package) {
+            if ($package->id == -1) {
+                throw new \RuntimeException("Fixed package ".$package->getName()." was not added to solver pool.");
+            }
+
             $this->addRulesForPackage($package, $ignorePlatformReqs);
 
             $rule = $this->createInstallOneOfRule(array($package), Rule::RULE_JOB_INSTALL, array(
diff --git a/src/Composer/DependencyResolver/Solver.php b/src/Composer/DependencyResolver/Solver.php
index 348b17c2b..2abcf5d8a 100644
--- a/src/Composer/DependencyResolver/Solver.php
+++ b/src/Composer/DependencyResolver/Solver.php
@@ -147,7 +147,6 @@ class Solver
                 if (abs($literal) !== abs($assertRuleLiteral)) {
                     continue;
                 }
-
                 $problem->addRule($assertRule);
                 $this->disableProblem($assertRule);
             }
diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index 6c94df10e..dea1e03e5 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -523,8 +523,6 @@ class Installer
             return array();
         }
 
-        ;
-
         $resultRepo = new ArrayRepository(array());
         $loader = new ArrayLoader(null, true);
         $dumper = new ArrayDumper();
diff --git a/tests/Composer/Test/Fixtures/installer/solver-problems.test b/tests/Composer/Test/Fixtures/installer/solver-problems.test
index b6d2180db..57d3ced92 100644
--- a/tests/Composer/Test/Fixtures/installer/solver-problems.test
+++ b/tests/Composer/Test/Fixtures/installer/solver-problems.test
@@ -61,12 +61,12 @@ Your requirements could not be resolved to an installable set of packages.
   Problem 2
     - The requested package bogus/pkg could not be found in any version, there may be a typo in the package name.
   Problem 3
-    - The requested package stable-requiree-excluded/pkg 1.0.1 exists as stable-requiree-excluded/pkg[1.0.0] but these are rejected by your constraint.
-  Problem 4
-    - The requested package stable-requiree-excluded/pkg (installed at 1.0.0, required as 1.0.1) is satisfiable by stable-requiree-excluded/pkg[1.0.0] but these conflict with your requirements or minimum-stability.
-  Problem 5
     - Installation request for requirer/pkg 1.* -> satisfiable by requirer/pkg[1.0.0].
     - requirer/pkg 1.0.0 requires dependency/pkg 1.0.0 -> no matching package found.
+  Problem 4
+    - stable-requiree-excluded/pkg is locked to version 1.0.0 and an update of this package was not requested.
+    - Same name, can only install one of: stable-requiree-excluded/pkg[1.0.0, 1.0.1].
+    - Installation request for stable-requiree-excluded/pkg 1.0.1 -> satisfiable by stable-requiree-excluded/pkg[1.0.1].
 
 Potential causes:
  - A typo in the package name