Asset Accounting Entries

Hi   --   The Asset Management Business Unit-US001 , has 4 Asset books ( CORP, FEDERAL, TAX and AMT).  Currently in CORP book  AM BU- US001  is tagged to  GL BU - US002, and CORP book is also the default book.

The scenario is User would like to tag  FEDERAL book to GL BU - US001, so there will be two books with two different GL BU's.

CORP               GLBU - US002               AM BU - US001               DEFAULT BOOK.

FEDERAL         GL BU - US001              AM BU - US001

Can user achieve the above scenario and generate correct accounting entries, is it possible.??

The reason for asking this is I tried to have a new GL BU for FEDERAL book, but there is an error message telling that the GL BU will be the BU which is there on CORP book which is default book.  I remember in previous versions prior to v 9.1, the user was able to change GL BU for individual books, But now the system automatically defaults the GL BU and it is greyed out so cannot be changed,