Here is what I got...

$ lsnrctl start

LSNRCTL for Solaris: Version 9.0.1.0.0 - Production on 27-OCT-2003 16:55:54

Copyright (c) 1991, 2001, Oracle Corporation. All rights reserved.

Starting /u01/app/oracle/product/9.1.0/bin/tnslsnr: please wait...

TNSLSNR for Solaris: Version 9.0.1.0.0 - Production
Log messages written to /u01/app/oracle/product/9.1.0/network/log/listener.log
Error listening on: (ADDRESS=(PROTOCOL=tcp)(PORT=1521))
TNS-12542: TNS:address already in use
TNS-12560: TNSrotocol adapter error
TNS-00512: Address already in use
Solaris Error: 125: Address already in use

Listener failed to start. See the error message(s) above...

$ lsnrctl status

LSNRCTL for Solaris: Version 9.0.1.0.0 - Production on 27-OCT-2003 16:56:13

Copyright (c) 1991, 2001, Oracle Corporation. All rights reserved.

Connecting to (ADDRESS=(PROTOCOL=tcp)(PORT=1521))
STATUS of the LISTENER
------------------------
Alias LISTENER
Version TNSLSNR for Solaris: Version 9.0.1.0.0 - Production
Start Date 20-OCT-2003 17:37:10
Uptime 6 days 23 hr. 19 min. 3 sec
Trace Level off
Security OFF
SNMP OFF
Listener Log File /u01/app/oracle/product/9.1.0/network/log/listener.log
Listening Endpoints Summary...
(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=db.wplink)(PORT=1521)))
Services Summary...
Service "wplp" has 1 instance(s).
Instance "wplp", status READY, has 1 handler(s) for this service...
The command completed successfully
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