diff --git a/phpBB/cron.php b/phpBB/cron.php
index fb85e9fe18..e179b3e8d6 100644
--- a/phpBB/cron.php
+++ b/phpBB/cron.php
@@ -48,7 +48,7 @@ function do_cron($cron_lock, $run_tasks)
 	}
 
 	// Unloading cache and closing db after having done the dirty work.
-	$cron_lock->unlock();
+	$cron_lock->release();
 	garbage_collection();
 }
 
@@ -74,7 +74,7 @@ else
 }
 
 $cron_lock = new phpbb_lock_db('cron_lock', $config, $db);
-if ($cron_lock->lock())
+if ($cron_lock->acquire())
 {
 	if ($config['use_system_cron'])
 	{
diff --git a/phpBB/includes/lock/db.php b/phpBB/includes/lock/db.php
index 092f4f9789..f5f1b4c6f9 100644
--- a/phpBB/includes/lock/db.php
+++ b/phpBB/includes/lock/db.php
@@ -80,11 +80,11 @@ class phpbb_lock_db
 	* @return	bool			true if lock was acquired
 	*							false otherwise
 	*/
-	public function lock()
+	public function acquire()
 	{
 		if ($this->locked)
 		{
-			return true;
+			return false;
 		}
 
 		if (!isset($this->config[$this->config_name]))
@@ -119,15 +119,15 @@ class phpbb_lock_db
 	/**
 	* Releases the lock.
 	*
-	* The lock must have been previously obtained, that is, lock() call
+	* The lock must have been previously obtained, that is, acquire() call
 	* was issued and returned true.
 	*
 	* Note: Attempting to release a lock that is already released,
-	* that is, calling unlock() multiple times, is harmless.
+	* that is, calling release() multiple times, is harmless.
 	*
 	* @return void
 	*/
-	public function unlock()
+	public function release()
 	{
 		if ($this->locked)
 		{
diff --git a/tests/lock/db_test.php b/tests/lock/db_test.php
index f60d7e3ee8..3b2e3ea3b2 100644
--- a/tests/lock/db_test.php
+++ b/tests/lock/db_test.php
@@ -32,52 +32,52 @@ class phpbb_lock_db_test extends phpbb_database_test_case
 
 	public function test_new_lock()
 	{
-		$this->assertTrue($this->lock->lock());
+		$this->assertTrue($this->lock->acquire());
 		$this->assertTrue(isset($this->config['test_lock']), 'Lock was created');
 
 		$lock2 = new phpbb_lock_db('test_lock', $this->config, $this->db);
-		$this->assertFalse($lock2->lock());
+		$this->assertFalse($lock2->acquire());
 
-		$this->lock->unlock();
+		$this->lock->release();
 		$this->assertEquals('0', $this->config['test_lock'], 'Lock was released');
 	}
 
 	public function test_expire_lock()
 	{
 		$lock = new phpbb_lock_db('foo_lock', $this->config, $this->db);
-		$this->assertTrue($lock->lock());
+		$this->assertTrue($lock->acquire());
 	}
 
 	public function test_double_lock()
 	{
-		$this->assertTrue($this->lock->lock());
+		$this->assertTrue($this->lock->acquire());
 		$this->assertTrue(isset($this->config['test_lock']), 'Lock was created');
 
 		$value = $this->config['test_lock'];
 
-		$this->assertTrue($this->lock->lock());
-		$this->assertEquals($value, $this->config['test_lock'], 'Second lock was ignored');
+		$this->assertFalse($this->lock->acquire());
+		$this->assertEquals($value, $this->config['test_lock'], 'Second lock failed');
 
-		$this->lock->unlock();
+		$this->lock->release();
 		$this->assertEquals('0', $this->config['test_lock'], 'Lock was released');
 	}
 
 	public function test_double_unlock()
 	{
-		$this->assertTrue($this->lock->lock());
+		$this->assertTrue($this->lock->acquire());
 		$this->assertFalse(empty($this->config['test_lock']), 'First lock is acquired');
 
-		$this->lock->unlock();
+		$this->lock->release();
 		$this->assertEquals('0', $this->config['test_lock'], 'First lock is released');
 
 		$lock2 = new phpbb_lock_db('test_lock', $this->config, $this->db);
-		$this->assertTrue($lock2->lock());
+		$this->assertTrue($lock2->acquire());
 		$this->assertFalse(empty($this->config['test_lock']), 'Second lock is acquired');
 
-		$this->lock->unlock();
+		$this->lock->release();
 		$this->assertFalse(empty($this->config['test_lock']), 'Double release of first lock is ignored');
 
-		$lock2->unlock();
+		$lock2->release();
 		$this->assertEquals('0', $this->config['test_lock'], 'Second lock is released');
 	}
 }