Yes, that’s true. And that’s why we hire people with experience in the specific technology and eventually form “centers of excellence” (CoE) around the more popular ones. We don’t always manage to do this, but our strategy is to hire very senior people first to create Centers of Excellence around them.
Currently, we can claim CoE around Java, .NET, J2ME, LAMP (including Python) and Lotus. That means that for each of these technologies, we have a number people with a mix of experience that can leverage each other.
Having said that, we work very hard at hiring people with a demonstrated ability to learn new technologies quickly and can just as quickly spot the strength and weaknesses in new technologies. Technology changes all the time and critical thinking is the skill for the long run.