Wrong, SQL Server 2000 Enterprise Edition support up to 4 nodes.

From Microsoft:

SQL Server 2000 Enterprise Edition and SQL Server 2000 Developer Edition support up to four nodes for failover clustering, including an Active/Active/Active/Active failover clustering configuration, up to 16 total instances. This means SQL Server 2000 Enterprise Edition and SQL Server 2000 Developer Edition are not supported on a cluster with more than four nodes even if SQL Server 2000 is not installed on more than four of the nodes.