Erm, I have 4.3.10 on a box here without any problems Slarty. You sure it isn't install-sensitive?

Oh, and serialize() and unserialize() *ARE* done quite frequently in "sane PHP apps". They serve a VERY specific purpose, but are generally one of the most efficient ways to ensure your PHP app is load balancable. Then again, I'm not talking about rinky dinky little blogging scripts, so for your uses it might not be an issue.