[Typo3] PHP 4.4.1 incompatible?

[He Shiming (NOSPAM)]

Dear All,

My hosting provider recently upgraded their PHP to version 4.4.1. My TYPO3 
site no longer works. The behavior is as followed:

1. The site's index page will load successfully
2. None of the other pages can be loaded, it'll load empty, and I'm using 
real-url

I had a chance to observe the error log. And there are these error messages:
 PHP Fatal error:  Cannot redeclare class t3lib_timetrack in 
class.t3lib_timetrack.php on line 88, referer:
PHP Fatal error:  Cannot redeclare class t3lib_timetrack in 
class.t3lib_timetrack.php on line 88, referer:

There are millions of this error.

The hosting provider claimed to have touched no settings. They've only 
upgraded the PHP.

What went wrong? How could I sort it out?

Best regards,
-- 
He Shiming