diff --git a/yii/requirements/YiiRequirementChecker.php b/yii/requirements/YiiRequirementChecker.php
index 160a5db..646d0d2 100644
--- a/yii/requirements/YiiRequirementChecker.php
+++ b/yii/requirements/YiiRequirementChecker.php
@@ -46,6 +46,9 @@ if (version_compare(PHP_VERSION, '4.3', '<')) {
  * );
  * ~~~
  *
+ * Note: this class definition does not match ordinary Yii style, because it should match PHP 4.3
+ * and should not use features from the older PHP version!
+ *
  * @property array|null $result the check results, this property is for internal usage only.
  *
  * @author Paul Klimov <klimov.paul@gmail.com>
@@ -62,7 +65,7 @@ class YiiRequirementChecker
 	 * If a string, it is treated as the path of the file, which contains the requirements;
 	 * @return YiiRequirementChecker self instance.
 	 */
-	public function check($requirements)
+	function check($requirements)
 	{
 		if (is_string($requirements)) {
 			$requirements = require($requirements);
@@ -106,7 +109,7 @@ class YiiRequirementChecker
 	 * Performs the check for the Yii core requirements.
 	 * @return YiiRequirementChecker self instance.
 	 */
-	public function checkYii()
+	function checkYii()
 	{
 		return $this->check(dirname(__FILE__) . DIRECTORY_SEPARATOR . 'requirements.php');
 	}
@@ -132,7 +135,7 @@ class YiiRequirementChecker
 	 * )
 	 * </code>
 	 */
-	public function getResult()
+	function getResult()
 	{
 		if (isset($this->result)) {
 			return $this->result;
@@ -145,7 +148,7 @@ class YiiRequirementChecker
 	 * Renders the requirements check result.
 	 * The output will vary depending is a script running from web or from console.
 	 */
-	public function render()
+	function render()
 	{
 		if (!isset($this->result)) {
 			$this->usageError('Nothing to render!');
@@ -166,7 +169,7 @@ class YiiRequirementChecker
 	 * @param string $compare comparison operator, by default '>='
 	 * @return boolean if PHP extension version matches.
 	 */
-	public function checkPhpExtensionVersion($extensionName, $version, $compare = '>=')
+	function checkPhpExtensionVersion($extensionName, $version, $compare = '>=')
 	{
 		if (!extension_loaded($extensionName)) {
 			return false;
@@ -183,7 +186,7 @@ class YiiRequirementChecker
 	 * @param string $name configuration option name.
 	 * @return boolean option is on.
 	 */
-	public function checkPhpIniOn($name)
+	function checkPhpIniOn($name)
 	{
 		$value = ini_get($name);
 		if (empty($value)) {
@@ -197,7 +200,7 @@ class YiiRequirementChecker
 	 * @param string $name configuration option name.
 	 * @return boolean option is off.
 	 */
-	public function checkPhpIniOff($name)
+	function checkPhpIniOff($name)
 	{
 		$value = ini_get($name);
 		if (empty($value)) {
@@ -214,7 +217,7 @@ class YiiRequirementChecker
 	 * @param string $compare comparison operator, by default '>='.
 	 * @return boolean comparison result.
 	 */
-	public function compareByteSize($a, $b, $compare = '>=')
+	function compareByteSize($a, $b, $compare = '>=')
 	{
 		$compareExpression = '(' . $this->getByteSize($a) . $compare . $this->getByteSize($b) . ')';
 		return $this->evaluateExpression($compareExpression);
@@ -226,7 +229,7 @@ class YiiRequirementChecker
 	 * @param string $verboseSize verbose size representation.
 	 * @return integer actual size in bytes.
 	 */
-	public function getByteSize($verboseSize)
+	function getByteSize($verboseSize)
 	{
 		if (empty($verboseSize)) {
 			return 0;
@@ -265,7 +268,7 @@ class YiiRequirementChecker
 	 * @param string|null $max verbose file size maximum required value, pass null to skip maximum check.
 	 * @return boolean success.
 	 */
-	public function checkUploadMaxFileSize($min = null, $max = null)
+	function checkUploadMaxFileSize($min = null, $max = null)
 	{
 		$postMaxSize = ini_get('post_max_size');
 		$uploadMaxFileSize = ini_get('upload_max_filesize');
@@ -292,7 +295,7 @@ class YiiRequirementChecker
 	 * @param boolean $_return_ whether the rendering result should be returned as a string
 	 * @return string the rendering result. Null if the rendering result is not required.
 	 */
-	public function renderViewFile($_viewFile_, $_data_ = null, $_return_ = false)
+	function renderViewFile($_viewFile_, $_data_ = null, $_return_ = false)
 	{
 		// we use special variable names here to avoid conflict when extracting data
 		if (is_array($_data_)) {
@@ -316,7 +319,7 @@ class YiiRequirementChecker
 	 * @param int $requirementKey requirement key in the list.
 	 * @return array normalized requirement.
 	 */
-	public function normalizeRequirement($requirement, $requirementKey = 0)
+	function normalizeRequirement($requirement, $requirementKey = 0)
 	{
 		if (!is_array($requirement)) {
 			$this->usageError('Requirement must be an array!');
@@ -354,7 +357,7 @@ class YiiRequirementChecker
 	 * This method will then terminate the execution of the current application.
 	 * @param string $message the error message
 	 */
-	public function usageError($message)
+	function usageError($message)
 	{
 		echo "Error: $message\n\n";
 		exit(1);
@@ -365,7 +368,7 @@ class YiiRequirementChecker
 	 * @param string $expression a PHP expression to be evaluated.
 	 * @return mixed the expression result.
 	 */
-	public function evaluateExpression($expression)
+	function evaluateExpression($expression)
 	{
 		return eval('return ' . $expression . ';');
 	}
@@ -374,7 +377,7 @@ class YiiRequirementChecker
 	 * Returns the server information.
 	 * @return string server information.
 	 */
-	public function getServerInfo()
+	function getServerInfo()
 	{
 		$info = isset($_SERVER['SERVER_SOFTWARE']) ? $_SERVER['SERVER_SOFTWARE'] : '';
 		return $info;
@@ -384,7 +387,7 @@ class YiiRequirementChecker
 	 * Returns the now date if possible in string representation.
 	 * @return string now date.
 	 */
-	public function getNowDate()
+	function getNowDate()
 	{
 		$nowDate = @strftime('%Y-%m-%d %H:%M', time());
 		return $nowDate;