Choosing different versions of Zend Framework to load using Zend_Loader and it's issues

Okay, so, I wanna be able to choose different versions of Zend Framework (and other frameworks) using Zend_Loader. Well, the code isn't tricky at all, but the problem is, there are so many require_once lines in the framework itself that would practically make the autoloader useless.

The Zend direct开发者_StackOverflow中文版ory has to be in the include_path which makes it a bit difficult to keep it there and also, all the require_once lines with non-absolute paths will have quite an impact on the application's performance, specially with my app which uses a lot of Zend classes on for processing each request.

I could strip out all the require_once lines manually or automatically, but I just have to do it all over again with each new 1.x.x release.

Any ideas?

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Stripping require_onces is not that hard, just running one line of code (saved as a script).

See this thread on Nabble for switching Zend Framework versions.

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See also native ZF support as of 1.10: http://framework.zend.com/manual/1.10/en/zend.loader.autoloader.html#zend.loader.autoloader.zf-version