OE Debug files getting overwritten

We are noticiing that OM is reusing the debug file names when generating debug logs.

This is occurring because of the following code in the OE_DEBUG package:

**************

if G_FILE is null then

         select substr('l'|| substr(to_char(sysdate,'MI'),1,1)

                || lpad(oe_debug_s.nextval,6,'0'),1,8) || '.dbg'

         into G_FILE

         from dual;

         G_FILE_PTR := utl_file.fopen(G_DIR, G_FILE, 'w');

         UTL_FILE.Put_Line(G_FILE_PTR,'Session Id:'||userenv('SESSIONID'));

***************

Because the package uses the substr function to truncate the value of the sequence, after the sequence exceeds 6 digits, the substr will return the same 6 digit value to be used as file name many times, overwriting preexisting files with the same name in the process.