Your not posting any links to see what you mean and as I clearly posted content meta and ajax are two separate things. The content meta is loaded in your header and ajax simply refreshes a page so it has no bearing on your content meta.
I can post a couple sites here http://www.reeftalk.com/gallery http://www.viperalley.com/gallery
There is no problem with ajax I hit MORE or anything else and the page simply refresh's and different thumbnails are shown. How does the content meta play into this?
If I view the page source before and after hitting an ajax thing and every single time here is my pages charset clearly printed
Content visible to verified customers only.
Therefore my suggestion to you since you have created your own language we do not support is to look at what you did. Without more info here I can not respond further. The content meta and ajax are completely separate things and have nothing to do with each other at all. One should not interfere with the other and from what I see by viewing any site is there is no bearing to this.