regarding v$diag_alert_ext

Oracle 11.2.0.3 SE-One 64-bit

Oracle Linux 5.6

While looking for ways to mine my listener logs I ran across a reference to v$diag_alert_ext  (message from Mladen Gogola at https://groups.google.com/forum/#!topic/comp.databases.oracle.server/g7vR99WS_jQ).

Looked intriguing.  No mention of it in the Reference manual.  And first attempt to pull anything useful ... hmm, not so much

SQL> select distinct(component_id) from v$diag_alert_ext

  2  ;

COMPONENT_ID

-------------------------------------------------------------------

clients

tnslsnr

rdbms

asm

SQL>

SQL> select count(*)

  2  from v$diag_alert_ext

  3  where component_id='tnslsnr'

  4  ;

  COUNT(*)

----------

         0