SQL> select banner from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod
PL/SQL Release 10.2.0.1.0 - Production
CORE 10.2.0.1.0 Production
TNS for 32-bit Windows: Version 10.2.0.1.0 - Production
NLSRTL Version 10.2.0.1.0 - Production

SQL> create table test2(
2 ACCT number(10),
3 dob DATE,
4 produ number(10));

Table created.

SQL> insert into test2 values (1,'12-MAR-08',1111);

1 row created.

SQL> ed
Wrote file afiedt.buf

1* insert into test2 values (2,'21-JAN-07',2222)
SQL> /

1 row created.

SQL> ed
Wrote file afiedt.buf

1* insert into test2 values (3,'21-JAN-07',3333)
SQL> /

1 row created.

SQL> select * from test2;

ACCT DOB PRODU
---------- --------- ----------
1 12-MAR-08 1111
2 21-JAN-07 2222
3 21-JAN-07 3333

I tried by pl/sql block like :

SQL> ed
Wrote file afiedt.buf

1 declare
2 amnt number :=0;
3 cursor c1 is select distinct dob from test2;
4 begin
5 for var in c1 loop
6 --select sum(produ) into amnt from test2 where dob = var.dob;
7 dbms_output.put_line(var.dob || ' ' );
8 end loop;
9* end;

SELECT  	   SUM(DECODE(DOB,'21-JAN-07',PRODU)) "21-JAN-07",
			   SUM(DECODE(DOB,'12-MAR-08',PRODU)) "12-MAR-08"
FROM TEST2