Slightly Off-topic: English to Spanish Translator

[Wayne Spivak]

Is there software for web based language translations of web sites, on
the fly?

I have an English based web site, and want to offer it in Spanish,
French and Dutch, but don't want to go to the expense of creating three
mirror sites.

There are on-line translators (Systran for example), that you can use
for a page by page translation, but this is cumbersome, as well as a
potential reason to loose the web-client.

Any ideas would be appreciated.