diff --git a/lib/public/appframework/http/jsonresponse.php b/lib/public/appframework/http/jsonresponse.php
index c6360e0a0f5a111f38c92322b92789c5378cecb2..c9c8696323d19b853a05b9cecd53ffa8ddbec938 100644
--- a/lib/public/appframework/http/jsonresponse.php
+++ b/lib/public/appframework/http/jsonresponse.php
@@ -49,7 +49,7 @@ class JSONResponse extends Response {
 	public function __construct($data=array(), $statusCode=Http::STATUS_OK) {
 		$this->data = $data;
 		$this->setStatus($statusCode);
-		$this->addHeader('Content-type', 'application/json; charset=utf-8');
+		$this->addHeader('Content-Type', 'application/json; charset=utf-8');
 	}
 
 
diff --git a/tests/lib/appframework/http/JSONResponseTest.php b/tests/lib/appframework/http/JSONResponseTest.php
index f7c89a9d2e1b3fb77109d48304d07945c7c6135c..06cd3410a6910be6cef5c2c5b3142ccadc010d4e 100644
--- a/tests/lib/appframework/http/JSONResponseTest.php
+++ b/tests/lib/appframework/http/JSONResponseTest.php
@@ -44,7 +44,7 @@ class JSONResponseTest extends \PHPUnit_Framework_TestCase {
 
 	public function testHeader() {
 		$headers = $this->json->getHeaders();
-		$this->assertEquals('application/json; charset=utf-8', $headers['Content-type']);
+		$this->assertEquals('application/json; charset=utf-8', $headers['Content-Type']);
 	}