Latest update of the openssl package from CentOS breaks Parallels Panel 9.x. The following errors are displayed in the /var/log/sw-cp-server/error_log file when Panel is trying to start:
# tail /var/log/sw-cp-server/error_log
2010-04-07 01:56:38: (log.c.75) server started
2010-04-07 01:56:38: (network.c.336) SSL: error:00000000:lib(0):func(0):reason(0)
2010-04-07 01:57:59: (log.c.75) server started
2010-04-07 01:57:59: (network.c.336) SSL: error:00000000:lib(0):func(0):reason(0)
2010-04-07 01:57:59: (log.c.75) server started
2010-04-07 01:57:59: (network.c.336) SSL: error:00000000:lib(0):func(0):reason(0)
2010-04-07 02:13:38: (log.c.75) server started
2010-04-07 02:13:38: (network.c.336) SSL: error:00000000:lib(0):func(0):reason(0)
2010-04-07 02:13:38: (log.c.75) server started
2010-04-07 02:13:38: (network.c.336) SSL: error:00000000:lib(0):func(0):reason(0) 
# service psa start
Starting xinetd service...                                            done
Starting named service...                                             done
Starting mysqld service...                                            done
Starting postgresql service...                                        not installed
Starting psa-spamassassin service...                                  done
Plesk: Starting Mail Server... already started
Starting mail handlers tmpfs storage
Starting Plesk...                                                     failed
Starting drwebd service...                                            not installed
#
To fix this you need to update Parallels Panel web-engine:
1. Download the appropriate package using the wget utility. Example for CentOS 5 x86:
#wget -c http://kb.parallels.com/Attachments/12669/Attachments/sw-cp-server-1.0-6.201004011105.centos5.i386.rpm
2. Install the downloaded package. Example for CentOS 5 x86:
#rpm -Uhv sw-cp-server-1.0-6.201004011105.centos5.i386.rpm
# rpm -Uhv sw-cp-server-1.0-6.201004011105.centos5.i386.rpm
Preparing...                ########################################### [100%]
Stoppping SWsoft control panels server... stale pidfile. [  OK  ]
   1:sw-cp-server           ########################################### [100%]
Starting SWsoft control panels server...[  OK  ]
-bash-3.2# service psa start
Starting xinetd service...                                            done
Starting named service...                                             done
Starting mysqld service...                                            done
Starting postgresql service...                                        not installed
Starting psa-spamassassin service...                                  done
Plesk: Starting Mail Server... already started
Starting mail handlers tmpfs storage
Starting Plesk...                                                     done
Starting drwebd service...                                            not installed
-bash-3.2# 
well, what can I say… The path for the error logs have solved my major issue…
Worked nicely for me! Thanks!
Cass