Changing the SQL isolation level in a query

If I run this code using a datawindow the isolation doesn't seem to be changed in the datawindow calls.

Test case 1

long ll_rows, ll_test

GTrans.Lock = 'SS'
dw_order_carton_info.settransobject( GTrans )
ll_rows = dw_order_carton_info.retrieve(21586146, 1)
messagebox('debug', 'SS ll_rows '+ string(ll_rows))

// Set back to read committed
GTrans.Lock = 'RC'
dw_order_carton_info.settransobject( GTrans )
ll_rows = dw_order_carton_info.retrieve(21586146, 1)
messagebox('debug', 'RC ll_rows '+ string(ll_rows))

If I call the SQL that is in the datawindow inline it will change the isolation level

Test case 2

long ll_rows, ll_test

GTrans.Lock = 'SS'
dw_order_carton_info.settransobject( GTrans )
select count(*)
into :ll_test
from table
using GTrans;

messagebox('debug', 'SS ll_rows '+ string(ll_rows))

// Set back to read committed
GTrans.Lock = 'RC'
dw_order_carton_info.settransobject( GTrans )
select count(*)
into :ll_test
from table
using GTrans;

messagebox('debug', 'RC ll_rows '+ string(ll_rows))

Is changing the isolation levels in test case 1 supported?

Resolved Changing the SQL isolation level in a query