Formatted data in data grid columns is being displayed erratically (4250942)

Formatted numbers using to_char(num,format) is being displayed erratically in data grid fields. This can be shown by setting up the followin test:

CREATE TABLE test1 (n NUMBER);

INSERT INTO test1
     VALUES (TO_NUMBER (3417));

INSERT INTO test1
     VALUES (TO_NUMBER (1215873));

INSERT INTO test1
     VALUES (TO_NUMBER (10215));

INSERT INTO test1
     VALUES (TO_NUMBER (895210));

INSERT INTO test1
     VALUES (TO_NUMBER (22841900));

INSERT INTO test1
     VALUES (TO_NUMBER (10));

INSERT INTO test1
     VALUES (TO_NUMBER (3715220639));

COMMIT;                                                                                        

Then run this query in the editor to produce a data grid:

The result is erratic behavior in the data grid column labeled N2. The data is neither left or right justified, but it also does not exactly appear to be centered. 

But if the select is run with the setup SQL as a script, it produces output that is consistent with SQL*Plus. The data is right-justified.