Colorbox ignores language (uses default)

When I open a node in Colorbox it doesn't take the language into account. It always opens the node in the default site language.

Case:
My site's default language is Dutch.
I have a view with a list of nodes in a particular language (in this case French). Each node in the list has a 'details' button which should show the node in a colorbox. The href is something like this: 'http://mysite/fr/investigation-policiere-et-judiciaire'.

The node does open in a colorbox window, but the language this node is shown in is in Dutch. The actual content is the right French content and the language of the node is also correctly displayed. But the result of $language->language is "nl" when I expect it to be "fr".

Because of this field names and other translated content (like the blue button) isn't shown in the right language. This is serious issue for this website.

I have added a screenshot which I hope describes this problem better than I can. :-)