Configure NAV 2009 SP1 for High Availability

I am long time SQL guy but relatively new to NAV. We currently have one server setup (NAVTest) with both app and database tiers, that works fine which was for testing and deployment. But now it is in production and I am still working on getting the production environment to work. I am trying to setup the three tiers with the client on terminal server (done and working great), the app tier on a pair of load balanced 2008 servers, (problems) and the database tier on a SQL 2008 cluster (problems).

Supposedly this is supported but I still have not completely got it set.

1. The NAV Database components won't install except on a local instance, it cannot find the cluster instance, however I copied the DLL and ran the stored procedures manually and I believe it is working since I have gotten the classic client to work.

2. If I run the RTC client locally on the application servers I can open NAV and connect to the database. If I use a RTC client on another machine and connect through the App servers either as the load balanced name or the individual name it fails and says Login Failed when connecting to SQL Server <DB0SQL>.

So I believe my issue is with the app server. I am trying to use domain accounts and have gotten to this point but I have not found much documentation and I am hoping someone out there has gotten this to work and has some advice or someone might have a suggestion. I have setup SPNs and delegation but the app server does not seam to be able to pass credentials through it so it may be a delegation issue.

Thanks for any documentation or advice.