Adam Lundrigan

Good catch :+1: Definitely looks to me like a strictness mismatch between the two classes: `ContentType::fromString` does not normalize the keyword while the Headers bag does. I'm not familiar enough...

@Freeaqingme how about other headers this class normalizes the field names of? Could we drop [that normalization](https://github.com/zendframework/zend-mail/blob/master/src/Headers.php#L524) for 3.0? Right now it's just shifting the problem from the header bag...

Is this still an issue? I tried this test case and it passes: ``` php public function testZendMvcIssue16() { $arr = [ 'Zend\View\Model\JsonModel' => ['application/json'], 'Zend\View\Model\FeedModel' => ['application/rss+xml'], ]; $header...

I also could not find a definitive answer on this. The Twitter docs had this to say: (Source: https://dev.twitter.com/overview/api/response-codes#Node--108, then scroll down a bit) > When the Twitter API returns...