Thank you for your post.
Our Development and Testing departments are aware of this issue. Other users on this forum have also reported the issue, as it appears to be related to the language the file was created. See the related post at:
I have attached your post to the original report, and I will keep you updated as more information becomes available.
I was going to suggest, as a workaround, basing your value list on a GetAsText() version of the date field. I'm not able to reproduce the original issue, though (running OS X 10.6.8 with FMP12.0v1). Tried making the value list based on any number of relationship types (=, ≥, X), and it always works as expected for me.
Edit: Oops, didn't refresh to see TSGal's post. Well then, never mind. :)
Thank you TSGal, and sorry for this duplicate.
Temporarily, we have used a text calculated field, but we have to make it YYYMMDD to keep the sort order, which is not really handy, especially here in Europe where we normally use DDMMYYYY
But let's hope it will be fixed soon...