we have ZCS 3.1.4 in our network. We had (very old) thin clients which supported only firefox 1/2. So we had to restrict to 3.1.4. ZCS 4 onwards require firefox 3 & above. Now we have upgraded our network nodes to the present day systems. Now we need help or assistance in upgrading to the present ZCS version. Is it worth the version upgrade route or install the latest version and import mails. For us mails are the only important items and not the other collaboration data.