PHP5.3.8怎么链接sql2008

sqlncli.msi已经安装 
php_sqlsrv_53_ts.dll已经配置  
xmapp apache也启动成功

但是出现以下错误:

Array ( [0] => Array ( [0] => IMSSP [SQLSTATE] => IMSSP [1] => -49 [code] => -49 [2] => This extension requires the Microsoft SQL Server 2011 Native Client. Access the following URL to download the Microsoft SQL Server 2011 Native Client ODBC driver for x86: http://go.microsoft.com/fwlink/?LinkId=163712 [message] => This extension requires the Microsoft SQL Server 2011 Native Client. Access the following URL to download the Microsoft SQL Server 2011 Native Client ODBC driver for x86: http://go.microsoft.com/fwlink/?LinkId=163712 ) [1] => Array ( [0] => IM002 [SQLSTATE] => IM002 [1] => 0 [code] => 0 [2] => [Microsoft][ODBC 驱动程序管理器] 未发现数据源名称并且未指定默认驱动程序 [message] => [Microsoft][ODBC 驱动程序管理器] 未发现数据源名称并且未指定默认驱动程序 ) )

web service

win2003 sp2

$conn=new com("Adodb.Connection");  
$connstr="Driver={Sql Server};Server=127.0.0.1;uid=sa;pwd=;database=dataname";
$conn->Open($connstr);