SQL & PL/SQL

I'm formatting a sqlplus report that will get loaded into Excel.
When you set a BREAK on a column, the colsep doesn't get printed before the blank rows:

set colsep ','
break on zip on dealer

select zip, dealer, make from some_table;

ZIP , DEALER ,MAKE
-----, ----------, ----------
12345,DEALER A ,CHEVY
,BUICK

Notice on the second line, you don't get the comma between zip and dealer columns.

Any suggestions for getting the comma on each row?

Thanks,
Klaus