Problem installing Joomla

[theywill]

Hi there,

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PRODUCT, VERSION, OPERATING SYSTEM, ARCHITECTURE

CentOS 64 5.5, Plesk 10.2


PROBLEM DESCRIPTION AND STEPS TO REPRODUCE

Can't install Joombla through Plesk.


ACTUAL RESULT

Error: Unable to install the app because its installation requirements are not met. Contact your hosting provider to resolve this problem.
.
Requirements
PHP extension
The 'mysql' extension was not found.

PHP extension
The 'zlib' extension was not found.

PHP extension
The 'xml' extension was not found.

EXPECTED RESULT

All of these extensions are installed, and I have confirmed that with PHP info. Also, I have another instance of Joomla running on the same server (different domain).

I've tried switching from Apache module to FastCGI and changing some of the other settings, but of course, that had no effect.


ANY ADDITIONAL INFORMATION


Advice?

Thank you,
James
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