It actually only seems to happen if direct path is used:
create table test_load (a number)
grant all on test_load to xxxxxxxxxxx
create public synonym test_load for test_load
INTO TABLE TEST_LOAD
FIELDS TERMINATED BY "," OPTIONALLY ENCLOSED BY '"'
TRAILING NULLCOLS (A)
Running the shell script gets:
SQL*Loader: Release 184.108.40.206.0 - Production on Tue Nov 22 10:09:13 2005
(c) Copyright 2001 Oracle Corporation. All rights reserved.
SQL*Loader-951: Error calling once/load initialization
ORA-00604: error occurred at recursive SQL level 1
ORA-00972: identifier is too long
Remove the "direct=true" or switch to a username/password@db combination with only 21 characters and it works.