Scope of jdbc realm glassfish 3.0.1
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Please I need some clarifications regarding jdbc realm in glassfish (v3) .
I am trying set up different login authentication for two application A and B located in the same domain.
I have successfully setup a jdbc realm authentication for my web application A.
But after creating a second web application B using the process (with different table, different jdbc realm name) it does not work for B. When i change the change to the jdbc realm name of A it works. 
   I am now confuse whether  I have made a mistake in the second Application B or not.
 To solve my problem I need the answer to the following questions ?

 1. Can I secure different application withing the same domain with each application having its own authentication ?
 2. Can I only have one jdbc realm per domain ?
 
 3. Can I only have one jdbc realm per Server ?
 thanks .
