application/javascript in IE

The application/javascript MIME type has stopped working in my copies of Internet Explorer (6 and 7). Both now silently ignore scripts linked with type="application/javascript", which is as far as I have since determined the behaviour most people experience. Indeed I've only found very sketchy reports of it working at all.

Because I had no idea I was unique in being able to experience scripts linked in the RFC-compliant and IANA-approved way, I have used this MIME type on quite a few sites. So it's good news, because I would never have spotted this otherwise. Happily, most of these sites are not yet deployed, and the rest only use Javascript for very trivial polish. There now begins a hunt to replace application/javascript with text/javascript on all my sites.

Obviously, I'm at a loss to explain why Microsoft has failed to offer a consistent platform for development and I feel quite aggrieved about it. If I hadn't already boycotted Internet Explorer this would be a pretty good reason to start.

On the assumption that some other piece of software has by accident or design disabled - or had previously enabled - application/javascript, this is my list of candidates:

1. Microsoft Outlook 2007, installed for the first time on this computer this week.
2. Word 2007, also installed this week for the first time.
3. Some random Windows update I installed last weekend.
4. Access 2007, installed two weeks ago (but I think I would have noticed sooner if that had caused this change).
5. Removing something malicious with Spybot. I think it removed one or two dubious registry entries left over from an infection of Vundo/VirtuMonde last year, so it's unlikely but there's an outside chance of an effect.