(via kb.parallels.com)
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_lo
2010-03-29 11:21:22: (log.c.75) server started
2010-03-29 11:21:22: (network.c.336) SSL: error:00000000:lib(0):func(0):
...
Resolution: It is necessary to update Parallels Panel web-engine.