Another community member has passed the PHP 5.3 Zend Certified Engineer exam (Sjoerd Massen) and has blogged about his experiences both before and during the exam.
Today I passed the exam to become a PHP 5.3 ZCE. Like everyone else I had to sign the non-disclosure contract so I can't go into detail about the questions that were asked, I can however tell my impressions of the exam and how prepared for it.
His preparations included going over some of the older sample tests and some additional study time on streams. He also mentions the PhpRiot iPhone/iPad application that helped him prepare as well as a few of the training courses he bought for certain topics. His overall impression of the exam was that it was more difficult, with plenty of open questions made for you to fill in an answer.