Dave Marshall, a developer from Hull, England, has posted a few recommendations he thinks could help you land that next PHP job.
After reading this thread, I thought I'd spend some time writing about what I feel are some measures you can take to landing a job in PHP. This first part is going to concentrate on the kind of technical matters I think any PHP developer should at least have knowledge of, if not some kind of experience.
He suggests: as much programming experience as possible, experience with the full development lifecycle, knowing how to work with external libraries and frameworks, being able to adapt to development tools, knowing web application security, and some work with web services and a touch of system administration. He's not saying that you have to have all of these - just that the more you know, the better off you could be.