Hi Andreas
Im facing precisely the same issue (SPS12) after adding a new realm and only for new realm users.
I can see in diagtool trace
com.sap.security.core.server.jaas.SPNegoLoginModule OPTIONAL ok exception true Trigger SPNEGO authentication.
#1 com.sap.security.spnego.legacy = false
#2 com.sap.spnego.creds_in_thread = true
#3 com.sap.spnego.jgss.name = j2ee-zz4@DOMAIN.LOCAL
where j2ee-zz4@DOMAIN.LOCAL is principal name of the already active realm that works perfectly
Please help !!!
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