[TYPO3] make typo3 survive server upgrade

[Bing Du]

Hi,

Here is our current configuration:

Typo3 4.0.6
RHEL 4
MySQL 4.x
PHP 4.x
Apache httpd 2.0.52

We're going to upgrade the typo3 server to:

Typo3 4.0.6 (no change)
RHEL 5
MySQL 5.x  (comes with RHEL 5 by default)
PHP 5.x (comes with RHEL 5 by default)
Apache httpd 2.x (comes with RHEL 5 by default)

Anybody has done this before and would like to share your experience?  I
want to be aware of potential pitfalls as many as possible before doing
upgrade.  I recall I've seen on the mailing list that some people on MySQL
5 were suggested to downgrade to MySQL 4 for compatibility issues, some
got blank screen due to server upgrade, etc.  Are there special
configurations needed on MySQL 5, PHP 5 or whatever in order to make typo3
work?  I'd appreciate any insights or pointers.

Thanks much in advance,

Bing