Fix getEncryption() issue for multiple client.

This is a workaround for [getEncryption() issue #5](https://github.com/hoaproject/Socket/issues/5)

I know is maybe not the best way, but after lot review I don't find how implement that otherwise.
That can be a good beginning for work on best way.

Best Regards.
You can probably reverse this condition (`else`-branch before the `if`-branch) and optimize this with the rest of the code (line 494 etc.)