If you're using node.js server should automatically serve client socket.io.js file, form the official wiki:
The client is served automatically by the Node.JS server. In your <head> tag of your HTML, include:
<script src="http://<uri:port>/socket.io/socket.io.js"></script>
If your web app and socket.io are on the same server and port, you can simply include:
<script src="/socket.io/socket.io.js"></script>
Socket.io client can also include optional version numbers, in order to maximize caching performance. You can simply include the version number within javascript filename;
<script src="/socket.io/socket.io.v0.0.1.js"></script>
If you choose to serve the client through other means, you can clone the socket.io-client repository and look at the dist/ subdirectory.
I'll look into that and change it asap!
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What server are you using (i mean code-wise, python, node.js etc..)?
Also, how did you manage to have multiple instances of the plugin? it should be pf_singleglobal?
Can you specify in more detail what was the actual error?