SQL 2005/2000 Cluster

Can we install an instance of SQL 2005 onto a cluster that already has an instance of SQL 2000 running on it?
you should be able to install a Yukon clustered instance on a cluster that already has SQL2K. A SQL Server 2005 failover cluster can reside on the same cluster as a SQL Server 2000 cluster. The only caveat is that if you remove the SQL Server 2005 failover cluster instance then you have to make sure the SQL Server SNAC (SQL Native Access Components) remains .. SNAC is what the SQL Server 2005 resource DLL uses to connect to SQL Server; the same resource DLL is used for both SQL Server 2005 clusters and SQL Server 2000 clusters (once SQL Server 2005 has been installed) and it’s left behind on uninstall for the remaining SQL Server 2000 failover cluster .. so SNAC has to be there for your SQL Server 2000 failover cluster to continue working.