Some dev environments get around these kinds of issues by using static analysis tools - StyleCop for .NET and Checkstyle for Java. If there are any for php, I'd suggest getting one.
Likewise, it doesn't so much matter what style you, or your company, uses - just that it stays consistent. If you can't find a static analysis tool for php, then just document known style issues (don't discuss it, just document what exists in current, stable source files that people haven't had style problems with) and call that the style guide.
This is an issue that can explode into all kinds of bikeshedding. It's important to not let it become an issue where people feel like they can provide input.
Toss that up onto your project wiki/shared folder/whatever and send out an e-mail to the team.
If you're not a lead/senior/someone with the authority to do this then give the doc to your lead and ask that they do it.
Enforce it, and change it as appropriate, in code reviews.