yiisoft/yii — pull request #1628 by DaSourcerer (2012-10-29 09:41:26+00:00)
Title: Fix for CHttpCacheFilter's Cache-Control headers being overwritten by started sessions

As reported [here](http://www.yiiframework.com/forum/index.php/topic/24036-caching-at-http-level/page__view__findpost__p__170135), there is a problem with the `Cache-Control` header being overwritten by PHP's session logic. This can result into situations where http caching loses its effects.

This PR sets a header via `session_cache_limiter()` which will be immediately overwritten. In addition, the `Pragma` header will be cleared as well. This seems to work well in PHP v5.4.x and according to [this comment](http://www.php.net/manual/de/function.session-cache-limiter.php#76398), it should work with previous versions of PHP too. I'd still appreciate some review by others.