Adventures with ASCP Direct loader

For most of the day today we were trying to figure out why the ASCP Direct loader was failing with this error:

APP-MRP-22130: Cannot connect to database

Cause: The current routine cannot connect to the database.

Action: Contact your system administrator or customer support representative.

Concurrent program returned no reason for failure.
ORACLE error 1012 in FDPCLS

Cause: FDPCLS failed due to ORA-01012: not logged on
.

The SQL statement being executed at the time of the error was: and was executed from the file .
$MSC_TOP/bin/MSCPLD.sh
Program exited with status 1

We had configured direct load as per metalink note 307443.1:
Set profile options in ASCP instance:
MRP:Use Direct Load Option = Yes
MSC: Launch System Sql Loader = Yes

Uncomment these lines from $MSC_TOP/bin/MSCPLD.sh and ensure that they are pointing to the 10.2.0 RDBMS ORACLE_HOME. 10g Database doesn't accept a loader from an Oracle home below 9.0

export ORACLE_HOME=10.2.0 ORACLE_HOME
export LD_LIBRARY_PATH=$ORACLE_HOME/lib;$ORACLE_HOME/ctx/lib:$LD_LIBRARY_PATH
export PATH=$ORACLE_HOME/bin:$PATH

However the error was occuring even after we relinked the MSCSLD binary. The following environment variables were already set as per metalink note 254810.1

# APS64_ORACLE_HOME=$MSO_TOP/bin/nls8174
# APS64_ORA_NLS33=$MSO_TOP/bin/nls8174/ocommon/nls/admin/data

Finally a truss of MSCSLD binary revealed that it was looking for ORA_NLS33 environment variable. After we set the environment variable as

ORA_NLS33=$MSO_TOP/bin/nls8174/ocommon/nls/admin/data

in the customization section of adovars.env

the issue got resolved.