YYYY-MM-DD date format not working (suddenly)

[Durkin]

I have a server that has just stopped accepting the YYYY-MM-DD date format when I access it from a client. I always use this date format for dates so even though I haven't used the server myself in maybe a week, I know that I have used this format on it before. Strangely, if I use QA on the server itself then YYYY-MM-DD works fine. I don't think it's the clients however because if I open a window to another server in QA on my own local machine then YYYY-MM-DD also works fine. I have noticed that the collation on these two machines is different but, as I say, I have used this date format on the problem machine befor. Thanks for any help, I'm baffled. Durkin