Kerio’s personal firewall has been rescued from extinction after the company revealed that it is selling the source code to Sunbelt Software.

The company had announced in October that it was to discontinue the product on the last day of 2005, with support continuing for a further year. The price being paid by Sunbelt to revive the product has not been announced.

As an interim measure, the Kerio Personal Firewall will be rebranded the “Sunbelt Kerio Personal Firewall”, a statement on the websites of both companies said.

Sunbelt has committed to continue development of the free version of the software for home users, believed to have been downloaded 2 million times since it first appeared in 2002.

Rival Zone Labs yesterday moved to steal Kerio customers, offering them a 40 percent discount on the $50 price of its ZoneAlarm Pro desktop firewall.

The offer is also good for users of Symantec’s Sygate Personal Firewall and Sygate Personal Firewall Pro, another software-based firewall that has recently hit the rocks. The company announced earlier this week that it was to be discontinued at the end of the year.

"A firewall is the most essential, fundamental element of protection against hackers," Laura Yecies, general manager of Zone Labs and vice president at Check Point affirmed.

With such competition in mind, new owners Sunbelt are to offer similar price concessions, though details have yet to be made public.

"We are thrilled to have it as part of our product line and Kerio users should know that we are firmly committed to continuing to provide world-class support for the product," said Sunbelt CEO said Alex Eckelberry.

Sunbelt Software was recently in the news after its CEO revealed that the publisher of a key-logging program had threatened to pursue the company under EU copyright law for altering users of its CounterSpy anti-spyware program to the key-logger’s existence on their PCs.

The company has a number of anti-spam and anti-spyware products in its line-up.