diff --git a/application/config/mimes.php b/application/config/mimes.php
index d806f69246..dd4d337334 100644
--- a/application/config/mimes.php
+++ b/application/config/mimes.php
@@ -116,7 +116,7 @@
 	'word'	=>	array('application/msword', 'application/octet-stream'),
 	'xl'	=>	'application/excel',
 	'eml'	=>	'message/rfc822',
-	'json'  =>	array('application/json', 'text/json'),
+	'json'  =>	array('application/json', 'text/json', 'text/plain'),
 	'pem'   =>	array('application/x-x509-user-cert', 'application/x-pem-file', 'application/octet-stream'),
 	'p10'   =>	array('application/x-pkcs10', 'application/pkcs10'),
 	'p12'   =>	'application/x-pkcs12',
diff --git a/tests/codeigniter/libraries/Upload_test.php b/tests/codeigniter/libraries/Upload_test.php
index 0d069d9a9d..c7f033dcba 100644
--- a/tests/codeigniter/libraries/Upload_test.php
+++ b/tests/codeigniter/libraries/Upload_test.php
@@ -195,6 +195,15 @@ function test_is_allowed_filetype()
 		$this->assertTrue($this->upload->is_allowed_filetype(FALSE));
 		$this->assertTrue($this->upload->is_allowed_filetype(TRUE));
 
+		$this->upload->allowed_types = array('json');
+		$this->upload->file_ext = '.json';
+		$this->upload->file_type = 'application/json';
+		$this->assertTrue($this->upload->is_allowed_filetype(FALSE));
+
+		$this->upload->file_type = 'text/plain';
+		$this->assertTrue($this->upload->is_allowed_filetype(FALSE));
+
+		$this->upload->allowed_types = array('html', 'gif');
 		$this->upload->file_temp = realpath(PROJECT_BASE.'tests/mocks/uploads/ci_logo.gif');
 		$this->upload->file_ext = '.gif';
 		$this->upload->file_type = 'image/gif';