Protect my PHP App

I have developed an app and its written in PHP (with a bunch of SQL scripts), this app will be used by a few small companies. For them to use it, I will have to install Apache and SQL Server for them.

Every method I开发者_StackOverflow社区 have thought has fallen short of what I need. I was actually just hoping to use ZendGuard or IonCube but they don't support PHP 5.3.x.

Is there a simpler method where I can maybe store a key in the database and make the app run only when it knows its on that server?

Maybe create a key based on some random numbers/letters and the machine name, sql server host name and encode/decode this when ever the system is in use?

Thanks all for any help or ideas

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Even if Zend and Ioncube don't support PHP 5.3 code (which I find hard to believe!! Are you sure?), I'm sure they will in the foreseeable future.

I think it's worth asking them when they are going to introduce support for it.

Update: It indeed seems true: Zend but then, the question is, does your software really need 5.3 (i.e. use 5.3 specific features like namespaces and such?)