just to know:
i have installed ISPconfig3 onto a linux server(not virtual) with Centos 5.4 with web&email services active (clamav, amavis, spamassassin,etc)..i think it will host about 30 joomla 1.5 web sites and manage about 60 email accounts (splitted in 30 different domains).
(i do not think visitors will be so many towards the websites)
the HW of the server is:
dual core intel Xeon 3.00 Ghz
1 GB RAM
..do you think is it suitable for the above tasks ?