使用Node.js处理文件路径问题

I'm deploying a node.js based application to IBM's Bluemix and have added a few features to one of the samples they provide. I've added an additional javascript file that makes an ajax call to PHP, but the PHP file is coming back as not found because my path is incorrect. I've tried putting the file everywhere and it's just not being found. I'm thinking (as a total node noobie) that I'm missing some mysterious configuration or something.I'm deploying a node.js based application to IB