tag plus tag

After updating my site this morning the multiple tag (tag+tag) query has stopped working for me.

So http://yourblog.com/tag/music+apple doesn’t work but http://yourblog.com/tag/music,apple does.

I have tried it as http://yourblog.com/?tag=music+apple as well, same result. http://yourblog.com/?tag=music,apple does work.

Just a single tag does work as well, http://yourblog.com/tag/music and http://yourblog.com/tag/apple

[moved to How to/Troubleshooting as this is not about an alpha or beta release]