In light of some of the current talk about dependency injection in PHP applications, Paul Jones has jumped on it and has posted on his blog about how his framework, Solar, already supports it.
Because it makes great use of dependecy injection, Solar has a standardized form of generating/retrieving dependency objects using its Solar::dependency() method.
The callilng code sends the dependency params to the target object at construction time. The target object then passes those params through Solar::dependency() to retrieve or create the dependency object.
Paul also briefly mentions that the parameters passed in can be: an object (including the dependency object itself), a string, or an array (treated internally as parameters to create a new object).