dear all :
 
       My environment is :
       
       tsm server 5.1.1 install on aix 433 platform
       tsm backup/archive client 5.1.1 install on SAP R/3 DB server
       tdp_r3 3.2.0.11 ( 64bit )  install on SAP R/3 4.6D with Oracle 8.1.7( 
64bit )

When I use SAP utility SAPDBA to perform online Database backup it was 
successful
When I use SAP utility SAPDBA to perform online Database backup with RMAN it 
was failed

I following the TDP for SAP R/3 installation guide. about TDP for SAP R/3 with 
RMAN Configuration .
linking oracle library . there is installation provide :
 
Example for Oracle 8.1:
cd $ORACLE_HOME/rdbms/lib
ln -s /usr/tivoli/tsm/tdp_r3/libobk.a /usr/lib/libobk.a
make -f ins_rdbms.mk ioracle LLIBOBK=/usr/lib/libobk.a

because my environemnt is Oracle 8.1.7 (64bit) so I doing the folowing command :
cd $ORACLE_HOME/rdbms/lib
ln -s /usr/tivoli/tsm/rdp_r3/ora64/libobk64.a /usr/lib/libobk64.a
make -f ins_rdbms.mk ioracle LLIBOBK=/usr/lib/libobk64.a

the online DB backup with RMAN error message . this error like Oracle was not 
right linking TDP R/3 library .
what can I to do . fix this probule .

thanks

RMAN> 2> 3> 4> 
RMAN-03022: compiling command: allocate
RMAN-03023: executing command: allocate
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03007: retryable error occurred during execution of command: allocate
RMAN-07004: unhandled exception during command execution on channel sbt_1
RMAN-10035: exception raised in RPC: ORA-19554: error allocating device, device 
type: SBT_TAPE, device name: 
ORA-19557: device error, device type: SBT_TAPE, device name: 
ORA-27000: skgfqsbi: failed to initialize storage subsystem (SBT) layer
Additional information: 4110
ORA-19511: SBT error = 4110, errno = 0, BACKUP_DIR environment variable is not s
et
RMAN-10031: ORA-19624 occurred during call to DBMS_BACKUP_RESTORE.DEVICEALLOCATE

RMAN> 
RMAN-03022: compiling command: list