Availability setup help needed

Hi!

We’re about to set up a biztalk 2004 solution for high availability. We will use 2 computers for a sql cluster and two computers for biztalk.
The orchistrations gets messages via http (and send messages via http).

We will set up biztalk on both machines and the SSO service as active on one of the biztalk machines (this machine will hold the Master secret) and passive on the other,
i.e. not clustered (this will be enough for our requirements).

Since we get messages sent to biztalk by another application via http, we will setup nlb to balance http request between the two biztalk machines.

I’ve read in the ‘Clustering the Master Secret Server’ (http://msdn.microsoft.com/library/default.asp?url=/library/en-us/deploying/htm/ebiz_depl_sso_aumt.asp) article
on msdn that \”Caution You cannot install the master secret server on a Network Load Balancing (NLB) cluster.\”, is this really true for the above setup? And if so, why and how should SSO be setup?

Thankful for any answers

/Rikard