I'm not sure this is the correct thread to post this in, and I don't expect to get a good answer as I don't think it's even possible. I'm looking for a way to create a single session login across multiple domains.

Basically I have a site that has several domains for the different countries like: .com, .co.uk, .co.jp, .tw, etc. I would like for the user to be able to login once and remain logged in if they go to a different language version of the site.

I have thought of some hackish ways to do this, but they are all just that, hackish. You can do the redirect to different sites upon login, but then you get the triple redirect which is ugly and has the potential to create a bunch of problems.

Does anyone else have sites that accomplish this in an elegant manner, or am I basically screwed? Any ideas would be great.

Thanks.

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