PHP Error when install 1.5.0

Please check this link

I don’t know why show this error.

PHP is not properly installed or configured at it seems. Please reinstall PHP or contact your hosting provider for more information.

But older version (1.4.9) working in same server. Please check

This is a problem with your PHP install itself.
You may need to forward the issue to your hosting manager, and if it’s your own server you will need to look at your php.ini file, and verify where the file is now located.