SQLTXPLAIN and ERROR at line 2: ORA-00905: missing keyword

Hello,

I am attempting to run an sqltxplain with bind variables for an SR I have with Oracle Support.  At the end of the log file, I get the following:

SQL>/
old   1: ^^explain_plan_for.
new   1: EXPLAIN PLAN SET statement_id = '28052' INTO sqltxplain.sqlt$_sql_plan_table FOR
old  14: SELECT /* ^^unique_id */
new  14: SELECT /* sqlt_s28052 */
var b1 varchar2(40);
*
ERROR at line 2:
ORA-00905: missing keyword

I will attach the file I am trying to execute, but it begins with the lines below:

var b1 varchar2(40);
var b2 varchar2(40);
var b3 varchar2(40);
var b4 varchar2(40);
var b5 varchar2(40);
var b6 varchar2(40);