depends on what you want: you might want to take a look at i18n.
YES exactly what i was looking for, but they mentioned mostly application, but i'm sure i can adapt the concept to the web also. Doesn't matter if i get a text format for both languages at least i won't double the pages on my server.
I've check on my side and fund a couple of php scripts and the translating google API, which are not reliable. Why ? because they translate word by word and at the end the sentence doesn't make any sense.
but thx buddy, i'll see what i can do with that concept.