PHP/MySQL development help

I run a number of web sites in the Internet marketing field, built mainly on PHP/MySQL, and sitting on a redhat linux dedicated server at Rackspace, with Plesk to manage the server.

I already have someone who maintains and updates my sites on an ongoing basis, and I'm looking to expand the team in order to complete and help with a number of ongoing projects.

I therefore need someone *based in the UK* proficient in PHP/MySQL, able to work on an ongoing basis during normal working hours, and who is willing to work with my existing developer.

The number of hours each week will vary depending on project levels, but ten or more hours a week is likely at first, and for the right candidate the work level is likely to rapidly increase as I have a number of projects on the go.

The right applicant should be proficient and experienced in PHP and MySQL, database design, and be able to work with business-critical live systems.

Some experience in Perl and Javascript, including AJAX, would also be an advantage.

The right individual will be well-motivated, professional in their approach, and committed to high standards of output.

I am looking for an immediate start - the first 4 weeks will be treated as a trial period, with the possibility of a long-term ongoing project for the right candidate.