diff --git a/tests/unit/suites/libraries/cms/html/JHtmlDateTest.php b/tests/unit/suites/libraries/cms/html/JHtmlDateTest.php
index 35027c1e3b72d..eccbb93cd66d1 100644
--- a/tests/unit/suites/libraries/cms/html/JHtmlDateTest.php
+++ b/tests/unit/suites/libraries/cms/html/JHtmlDateTest.php
@@ -26,7 +26,7 @@ class JHtmlDateTest extends PHPUnit_Framework_TestCase
 	public function dataTestRelative()
 	{
 		$now1 = new JDate('now');
-		sleep(1);
+		usleep(1);
 		$now2 = new JDate('now');
 
 		return array(
diff --git a/tests/unit/suites/libraries/joomla/JFactoryTest.php b/tests/unit/suites/libraries/joomla/JFactoryTest.php
index 1370abf5f79c5..40fb0f4d5f4e5 100644
--- a/tests/unit/suites/libraries/joomla/JFactoryTest.php
+++ b/tests/unit/suites/libraries/joomla/JFactoryTest.php
@@ -223,7 +223,7 @@ public function testGetDateNow()
 		JFactory::$language = $this->getMockLanguage();
 
 		$date = JFactory::getDate('now');
-		sleep(1);
+		usleep(1);
 		$date2 = JFactory::getDate('now');
 
 		$this->assertThat(