Gusgsm - 4:16 pm on Feb 25, 2011 (gmt 0)
I agree with what has been said before. I would like to add a word of caution: If you finally go Drupal, go version 6 and not 7.
Why? Because 7 is going to be rather good, probably much better than 6. But it's not ready yet because of the lack of contributed modules, some of which (views, pathauto, CKK variants...) I am almost sure you are going to need (as somebody said, if you do not need them, it's likely you don't need Drupal 'so much' as your client thinks).
Drupal 6 is as mature and stable as it can be and it's extremely flexible and has been proven in many kind of sites.
It's multilingual ability is good, although it's not as good (ie: easy to manage and tweak) as I would like myself.
Another word of caution: It's RAM hungry. I just changed my hosting (a very modest one) because of that into a virtual hosting with 128 Mb for each of my sites. Luckyly there are plenty of solutions with machines 'in the cloud' nowadays that are rather well-priced.