Fatal Error: no matching class connection

index.php

<?php
   import database.connection;
   $connection = connection::get()->getPersistenceManager(); // ***ERROR HERE***
?>

connection.java

package database;

import javax.jdo.JDOHelper;
import javax.jdo.PersistenceManagerFactory;

public final class connection {
    private static final PersistenceManagerFactory pmfInstance =
        JDOHelper.getPersistenceManagerFactory("transactions-optional");

    private connection() {}

    public static PersistenceManagerFactory get() {
        return pmfInstance;
    }
}

Quercus is otherwise configured fine, PHP implementation works smoothly on GAE. But when I try to initialize classes, PHP can't find them. What am I doing wrong?