Description:
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When I want to create a class which extends HttpResponse class, then php crashes. My php version is 5.1.2.

It is not a problem with php or windows platform, because I can create class which extends e.g. HttpRequest;

Reproduce code:
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class TestClass extends HttpResponse {
}

TestClass::setContentDisposition("test.txt");

Expected result:
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Should work...

Actual result:
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PHP/Apache crash