I had that problem last night, but at the moment everything seems fine *fingers crossed*

That should answer everything
by Tech Bloke at Winsocket
1. Are there any specific limitations in terms of software that we can run on the server? (PHP4, Perl, IRC, mail etc)
No, there are no limitations, it functions exactly like a dedicated server. You can run any legally licensed software that you want.
2. What spec is the machine that the virtual servers run on?
Multi-processor, 4GB RAM, Multiple 10K RPM SCSI hard drives in a RAID array.
3. How many virtual servers per host machine?
No more than 4 per CPU.