If you thought it’s no problem to retrive the users timezone from a http request you are wrong.

You get the locale but not the timezone and if you try to create the timzone from this locale you will get the default timezone from the server.

Currently there are two ways to get the timezone:

1. expensive geolocation service like http://www.ip2location.com/
2. javascript as discribed at http://www.onlineaspect.com/

I don’t like both solutions, therefore i created a third one by mapping the locales to timzones. This solution doesn’t work for countries with more than one timezone but thats ok for my requirements.