pdo errors since moving hosts?

I moved my site to a new host yesterday. Everything seems to be working fine, but the error_log file is rapidly expanding with this message every few minutes:

[08-Sep-2009 19:13:27] PHP Warning: PHP Startup: Unable to load dynamic library ‘/usr/local/lib/php/extensions/no-debug-non-zts-20060613/pdo_sqlite.so’ – /usr/local/lib/php/extensions/no-debug-non-zts-20060613/pdo_sqlite.so: undefined symbol: php_pdo_unregister_driver in Unknown on line 0

I’ve seen another post about similar errors so I contacted my host. They say that PDO MySQL isn’t supported, so disable any plugins that are trying to use it.

But I don’t think any of my plugins are causing the problem?

I’m using: Akismet, All in One SEO, Feedburner Feedsmith, Formbuilder, Google Analyticator, Google XML Sitemaps, Sociable, Tagline Rotator and WordPress Popular Posts.

A Google search on ‘unable to load sqlite.so’ shows lots of cached WordPress error logs with the same error, so must be quite a common problem?

My hosting does use PHP 5

Any advice would be welcomed – many thanks!