diff --git a/lib/Cake/Test/Case/Utility/CakeNumberTest.php b/lib/Cake/Test/Case/Utility/CakeNumberTest.php
index 25737679f..c1bf0188c 100644
--- a/lib/Cake/Test/Case/Utility/CakeNumberTest.php
+++ b/lib/Cake/Test/Case/Utility/CakeNumberTest.php
@@ -529,8 +529,8 @@ class CakeNumberTest extends CakeTestCase {
  * @dataProvider filesizes
  * @return void
  */
-	public function testFromReadableSize($size, $expected) {
-		$result = $this->Number->fromReadableSize($size);
+	public function testFromReadableSize($params, $expected) {
+		$result = $this->Number->fromReadableSize($params['size'], $params['default']);
 		$this->assertEquals($expected, $result);
 	}
 
@@ -541,7 +541,7 @@ class CakeNumberTest extends CakeTestCase {
  * @return void
  */
 	public function testFromReadableSizeException() {
-		$result = $this->Number->fromReadableSize('bogus');
+		$result = $this->Number->fromReadableSize('bogus', false);
 	}
 
 /**
@@ -551,14 +551,15 @@ class CakeNumberTest extends CakeTestCase {
  */
 	public function filesizes() {
 		return array(
-			array('512B', 512),
-			array('1KB', 1024),
-			array('1.5KB', 1536),
-			array('1MB', 1048576),
-			array('1.5MB', 1572864),
-			array('1GB', 1073741824),
-			array('1.5GB', 1610612736),
-			array('512', 512),
+			array(array('size' => '512B', 'default' => false), 512),
+			array(array('size' => '1KB', 'default' => false), 1024),
+			array(array('size' => '1.5KB', 'default' => false), 1536),
+			array(array('size' => '1MB', 'default' => false), 1048576),
+			array(array('size' => '1.5MB', 'default' => false), 1572864),
+			array(array('size' => '1GB', 'default' => false), 1073741824),
+			array(array('size' => '1.5GB', 'default' => false), 1610612736),
+			array(array('size' => '512', 'default' => 'Unknown type'), 512),
+			array(array('size' => '2VB', 'default' => 'Unknown type'), 'Unknown type')
 		);
 	}
 
diff --git a/lib/Cake/Utility/CakeNumber.php b/lib/Cake/Utility/CakeNumber.php
index d12b4f90a..db3f51a70 100644
--- a/lib/Cake/Utility/CakeNumber.php
+++ b/lib/Cake/Utility/CakeNumber.php
@@ -105,9 +105,10 @@ class CakeNumber {
  * Converts filesize from human readable string to bytes
  *
  * @param string $size Size in human readable string like '5MB'
+ * @param mixed $default Value to be returned when invalid size was used, for example 'Unknown type'
  * @return integer Bytes
  */
-	public static function fromReadableSize($size) {
+	public static function fromReadableSize($size, $default = false) {
 		if (ctype_digit($size)) {
 			return $size * 1;
 		}
@@ -120,6 +121,9 @@ class CakeNumber {
 		if (substr($size, -1) == 'B' && ctype_digit(substr($size, 0, strlen($size) - 1))) {
 			return $size * 1;
 		}
+		if ($default !== false) {
+			return $default;
+		}
 		throw new CakeException(__d('cake_dev', 'No unit type.'));
 	}