[Costin Trifan]

The advantage of opensource is also that you can modify the code yourself (or pay someone else to modify it), so this gives you more flexibility than a proprietary system would normally provide.

oh, yeah, you're right on this one and I couldn't agree with you more! but I wasn't meaning this when I said what I said. Suppose you have no knowledge or skills whatsoever then what can a free (maybe not even supported anymore) cms can do for your website?

It will work ok until you get(if you get) a high traffic of visitors. Then you'd like to customize it and that will be, sometimes, pretty hard...