MySQL is not allowing ON UPDATE CURRENT_TIMESTAMP for a DATETIME field

Question

I have seen a lot of related questions, but I cannot place my finger on this specific question:

I have a MySQL table with both a TIMESTAMP (for when the field was create

Answer 1

That feature appears to have been introduced in 5.6. Works as expected on my default OS X install.

Reference: Automatic Timestamp Properties Before MySQL 5.6.5