Visto is continuing to flex its intellectual property muscle, saying today it has filed its second patent-infringement lawsuit against a wireless e-mail provider. This time, instead of attacking an industry giant like Microsoft, it’s suing one of its fellow start-ups, Good Technology.

Visto filed suit in the U.S. District Court in the Eastern District of Texas, claiming that Good has infringed on multiple Visto patents. In fact, Visto is claiming that Good is a late entrant into the wireless e-mail space and has no patents related to the technology. Visto is seeking both monetary damages and a permanent injunction against Good to stop selling its GoodLink e-mail service--the petition similar to that made by NTP to shut down Research in Motion’s BlackBerry service.

“We have made tremendous technological and financial investments since 1996 and we refuse to allow others to benefit from our hard work and commitment to innovation,” Visto chairman and CEO Brian Bogosian said in a statement.

A spokesperson for Good said that the company has not yet seen the lawsuit. “Until we have an opportunity to see and review this complaint, we're not in a position to comment on it,” the spokesperson said via e-mail.

Last month, Visto sued Microsoft claiming its new Windows Mobile 5.0 platform violated related patents. And last April Visto filed a lawsuit against Seven, claiming similar infringement. While being aggressive against competitors, Visto has also taken steps to insulate itself against other companies’ lawsuits. Just before suing Microsoft, Visto reached a licensing agreement with NTP, heading off the possibility of litigation between the two companies. With RIM and NTP back in court and the increasing likelihood that the BlackBerry service will go dark, competing e-mail providers are scrambling both to lure away Blackberry customers and protect their own backs. Bogosian said then that while it doesn’t believe that Visto’s solution is infringing on any of NTP’s patents, it partnered with the NTP to dispel even the notion of a possible litigation between the companies.

“There are justifiable marketplace jitters about whether BlackBerry service will be shut down by a federal court next month,” Bogosian said in today’s statement. “With Visto, all users, including BlackBerry users, have a safe harbor alternative to RIM that offers protection from intellectual property risks.”

The landmark battle NTP and RIM has set is expected to set off even more litigation in months to come, but while lawsuits aren’t good for any company, they are a sign that push e-mail has evolved from a niche market into a massive business, said Jill Stelfox, CEO of Defywire, a Virginia-based company that provides e-mail and data solutions to vertical markets.

“Moving wireless data is not really a new concept, but it’s becoming a big concept,” Stelfox said. “I don’t know when all of this litigation will end, but the good news is it demonstrates that there is a lot of value in this space.”