Json feed mime type issue

Internet Explorer 11 (I did not tested other versions) currently blocks ZC json feeds in Ajax requests (for example, when it's used with JQuery getJSON() and probably the ZCML script proposed by Stephen here because it is also based on JSON feed parsing) and the issue is a type mismatch. This is the message from the IE developer tools console:

<url> was blocked due to mime type mismatch (<url> stands for the current json feed url)

In Chrome the json feed is not blocked, but the following message appears in console :

Resource interpreted as Script but transferred with MIME type text/plain

I think that the json feed should have application/json as mime type instead of text/plain - please fix this as soon as possible. Some of my current scripts which previously worked are currently blocked by IE

Regards,
George