diff --git a/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php b/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php
index 517fd0036..ceacc9638 100644
--- a/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php
+++ b/lib/Doctrine/ORM/Query/ResultSetMappingBuilder.php
@@ -47,15 +47,25 @@ class ResultSetMappingBuilder extends ResultSetMapping
      *
      * @param string $class The class name of the root entity.
      * @param string $alias The unique alias to use for the root entity.
-     * @param string $prefix Prefix for columns
+     * @param array $renamedColumns Columns that have been renamed (tableColumnName => queryColumnName)
      */
-    public function addRootEntityFromClassMetadata($class, $alias, $prefix = '')
+    public function addRootEntityFromClassMetadata($class, $alias, $renamedColumns = array())
     {
         $this->addEntityResult($class, $alias);
         $classMetadata = $this->em->getClassMetadata($class);
+        if ($classMetadata->isInheritanceTypeSingleTable() || $classMetadata->isInheritanceTypeJoined()) {
+            throw new \InvalidArgumentException('ResultSetMapping builder does not currently support inheritance.');
+        }
         $platform = $this->em->getConnection()->getDatabasePlatform();
         foreach ($classMetadata->getColumnNames() AS $columnName) {
-            $this->addFieldResult($alias, $platform->getSQLResultCasing($prefix . $columnName), $classMetadata->getFieldName($columnName));
+            $propertyName = $classMetadata->getFieldName($columnName);
+            if (isset($renamedColumns[$columnName])) {
+                $columnName = $renamedColumns[$columnName];
+            }
+            if (isset($this->fieldMappings[$columnName])) {
+                throw new \InvalidArgumentException("The column '$columnName' conflicts with another column in the mapper.");
+            }
+            $this->addFieldResult($alias, $platform->getSQLResultCasing($columnName), $propertyName);
         }
     }
 
@@ -66,15 +76,25 @@ class ResultSetMappingBuilder extends ResultSetMapping
      * @param string $alias The unique alias to use for the joined entity.
      * @param string $parentAlias The alias of the entity result that is the parent of this joined result.
      * @param object $relation The association field that connects the parent entity result with the joined entity result.
-     * @param string $prefix Prefix for columns
+     * @param array $renamedColumns Columns that have been renamed (tableColumnName => queryColumnName)
      */
-    public function addJoinedEntityFromClassMetadata($class, $alias, $parentAlias, $relation, $prefix = '')
+    public function addJoinedEntityFromClassMetadata($class, $alias, $parentAlias, $relation, $renamedColumns = array())
     {
         $this->addJoinedEntityResult($class, $alias, $parentAlias, $relation);
         $classMetadata = $this->em->getClassMetadata($class);
+        if ($classMetadata->isInheritanceTypeSingleTable() || $classMetadata->isInheritanceTypeJoined()) {
+            throw new \InvalidArgumentException('ResultSetMapping builder does not currently support inheritance.');
+        }
         $platform = $this->em->getConnection()->getDatabasePlatform();
         foreach ($classMetadata->getColumnNames() AS $columnName) {
-            $this->addFieldResult($alias, $platform->getSQLResultCasing($prefix . $columnName), $classMetadata->getFieldName($columnName));
+            $propertyName = $classMetadata->getFieldName($columnName);
+            if (isset($renamedColumns[$columnName])) {
+                $columnName = $renamedColumns[$columnName];
+            }
+            if (isset($this->fieldMappings[$columnName])) {
+                throw new \InvalidArgumentException("The column '$columnName' conflicts with another column in the mapper.");
+            }
+            $this->addFieldResult($alias, $platform->getSQLResultCasing($columnName), $propertyName);
         }
     }
 }
\ No newline at end of file
diff --git a/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php b/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
index 1b1a713b8..2a09b8310 100644
--- a/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
+++ b/tests/Doctrine/Tests/ORM/Functional/NativeQueryTest.php
@@ -7,6 +7,8 @@ use Doctrine\ORM\Query\ResultSetMappingBuilder;
 use Doctrine\Tests\Models\CMS\CmsUser;
 use Doctrine\Tests\Models\CMS\CmsPhonenumber;
 use Doctrine\Tests\Models\CMS\CmsAddress;
+use Doctrine\Tests\Models\Company\CompanyFixContract;
+use Doctrine\Tests\Models\Company\CompanyEmployee;
 
 require_once __DIR__ . '/../../TestInit.php';
 
@@ -177,8 +179,8 @@ class NativeQueryTest extends \Doctrine\Tests\OrmFunctionalTestCase
 
         $rsm = new ResultSetMappingBuilder($this->_em);
         $rsm->addRootEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsUser', 'u');
-        $rsm->addJoinedEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsPhonenumber', 'p', 'u', 'phonenumbers', 'p_');
-        $query = $this->_em->createNativeQuery('SELECT u.*, p.phonenumber AS p_phonenumber FROM cms_users u INNER JOIN cms_phonenumbers p ON u.id = p.user_id WHERE username = ?', $rsm);
+        $rsm->addJoinedEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsPhonenumber', 'p', 'u', 'phonenumbers');
+        $query = $this->_em->createNativeQuery('SELECT u.*, p.* FROM cms_users u LEFT JOIN cms_phonenumbers p ON u.id = p.user_id WHERE username = ?', $rsm);
         $query->setParameter(1, 'romanb');
 
         $users = $query->getResult();
@@ -216,9 +218,9 @@ class NativeQueryTest extends \Doctrine\Tests\OrmFunctionalTestCase
 
         $rsm = new ResultSetMappingBuilder($this->_em);
         $rsm->addRootEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsUser', 'u');
-        $rsm->addJoinedEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsAddress', 'a', 'u', 'address', 'a_');
+        $rsm->addJoinedEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsAddress', 'a', 'u', 'address', array('id' => 'a_id'));
 
-        $query = $this->_em->createNativeQuery('SELECT u.id, u.name, u.status, a.id AS a_id, a.country AS a_country, a.zip AS a_zip, a.city AS a_city FROM cms_users u INNER JOIN cms_addresses a ON u.id = a.user_id WHERE u.username = ?', $rsm);
+        $query = $this->_em->createNativeQuery('SELECT u.*, a.*, a.id AS a_id FROM cms_users u INNER JOIN cms_addresses a ON u.id = a.user_id WHERE u.username = ?', $rsm);
         $query->setParameter(1, 'romanb');
 
         $users = $query->getResult();
@@ -234,5 +236,15 @@ class NativeQueryTest extends \Doctrine\Tests\OrmFunctionalTestCase
         $this->assertEquals(10827, $users[0]->getAddress()->getZipCode());
         $this->assertEquals('Berlin', $users[0]->getAddress()->getCity());
     }
+
+    /**
+     * @expectedException \InvalidArgumentException
+     */
+    public function testRSMBuilderThrowsExceptionOnColumnConflict()
+    {
+        $rsm = new ResultSetMappingBuilder($this->_em);
+        $rsm->addRootEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsUser', 'u');
+        $rsm->addJoinedEntityFromClassMetadata('Doctrine\Tests\Models\CMS\CmsAddress', 'a', 'u', 'address');
+    }
 }