just in case, the output from requirements.php
PHP version Passed Yii Framework PHP 5.1.0 or higher is required.
$_SERVER variable Passed Yii Framework
Reflection extension Passed Yii Framework
PCRE extension Passed Yii Framework
SPL extension Passed Yii Framework
DOM extension Passed CWsdlGenerator
PDO extension Passed All DB-related classes
PDO SQLite extension Warning All DB-related classes This is required if you are using SQLite database.
PDO MySQL extension Passed All DB-related classes This is required if you are using MySQL database.
PDO PostgreSQL extension Warning All DB-related classes This is required if you are using PostgreSQL database.
Memcache extension Warning CMemCache
APC extension Warning CApcCache
Mcrypt extension Warning CSecurityManager This is required by encrypt and decrypt methods.
SOAP extension Warning CWebService, CWebServiceAction
GD extension Passed CCaptchaAction
sorry for the output, it's a little kaos, but all is there