How to append timestamp to log file in SQL*Plus ?

Question

Version: 11.2.0.3
Platform : RHEL 5.8 (But I am looking for platform independant solution)
I want to append the timestamp to spooled log file name in SQL*Plus.
The spooled log filename should look like
WMS_APP_23-March-2013.logI tried the following 3 methods found in the google. But none of them worked !
I tried this
col sysdt noprint new_value sysdt_var
SELECT TO_CHAR(SYSDATE, 'yyyymmdd_hh24miss') sysdt FROM DUAL;
spool run_filename_&sysdt_var.Logas suggested in
http://power2build.wordpress.com/2011/03/11/sqlplus-spool-name-with-embedded-timestamp/
and this
spool filename with timestamp
col sysdt noprint new_value sysdt
SELECT TO_CHAR(SYSDATE, 'yyyymmdd_hh24miss') sysdt FROM DUAL;
spool run_filename_&sysdt..Logas suggested in
http://powerbuildev.wordpress.com/2011/03/11/sqlplus-spool-name-with-embedded-timestamp/
and this
column tm new_value file_time noprint
select to_char(sysdate, 'YYYYMMDD') tm from dual ;
prompt &file_time
spool logfile_id&file_time..logas suggested in
Creating a spool file with date/time appended to file name
None of the above worked in RHEL or MS DOS. Any workaround ?

Answer 1

I have tested your suggestions. But I still couldn't append the date to the logfile in RHEL or MS DOS SQL*Plus
Here are the attempts I've made. I am posting how the logfile looked like after every test.
#Attempt1 with two dots (&sysdate..log )
set echo on
set feedback on
set define off
set pages 999
column dcol new_value SYSDATE noprint
select to_char(sysdate,'YYYYMMDD') dcol from dual;
spool testlog.&sysdate..log
select 'hello' from dual;
spool off;Log File Name -- > testlog.&sysdate..log
#Attempt2 with single dot (&sysdate.log)
set echo on
set feedback on
set define off
set pages 999
column dcol new_value SYSDATE noprint
select to_char(sysdate,'YYYYMMDD') dcol from dual;
spool testlog.&sysdate.log
select 'hello' from dual;
spool off;Log File Name ---> testlog.&sysdate.log
#Attempt3. Replacing first dot with Hyphen (testlog- ) to check if the first dot was causing the issue
set echo on
set feedback on
set define off
set pages 999
column dcol new_value SYSDATE noprint
select to_char(sysdate,'YYYYMMDD') dcol from dual;
spool testlog-&sysdate.log
select 'hello' from dual;
spool off;Log Filename: testlog-&sysdate.log
#Attempt4: replacing SYSDATE with SDATE
set echo on
set feedback on
set define off
set pages 999
column dcol new_value SDATE noprint
select to_char(sysdate,'YYYYMMDD') dcol from dual;
spool testlog1.&SDATE..log
select 'hello' from dual;
spool off;Log File Name -- > testlog1.&SDATE..log