SSO bi4 AIX with multi domain

hi,

I setted the SSO AND <->SAP BI4.1 SP5 (on AIX server) I created an account service boservice with the first domain domain1 and I can get AD users in CMC

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after the  automatic login  it works fine in sap bi4 Image may be NSFW.
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now my company want to use a SSO for another domain domain2 ! what is the steps to do this requirements ?

I found only a sap notes for 3.x but nothing for 4.1

I have two questions:

1. what do I do  to get a users from the second domain domain2  in CMC (must I create the same service account boservice2 in the second domain or only give him approbation to get user for this domain
2. should I add a  line for the global.properties to specify the second domain
3. Have you a step by step document, I am very confused

Regards,