A landmark legal battle is looming over the use of the word "spam" by companies offering junk email blocking services.

Hormel Foods, the makers of the luncheon meat made famous by a Monty Python sketch, is challenging a Seattle-based technology firm that wants to trademark "Spam Arrest" - the name of its software for email users.

Brian Cartmell, president and chief executive of SpamArrest LLC, said: "Hormel is acting like a corporate crybaby and ought to can it.

"Spam is a common term describing unsolicited commercial email (UCE). Dozens of companies use the word spam in their legal and commercial names and no one confuses any of us with the Hormel canned meat product."

He points to the fact that Hormel itself says on its website: "We do not object to use of this slang term to describe UCE, although we do object to the use of our product image in association with that term."

But the food company, which produces a wide range of ready meals and meat products, has challenged Spam Arrest's applications to trademark its own company name.

In an objection filed to the US Patent and Trademark Office, Hormel argues it has built up "substantial goodwill and good reputation" for the Spam brand name, which would be damaged by Spam Arrest's use of the term.

According to a report in today's Washington Post, the company said that Spam Arrest's name so closely resembles that of its lunch meat that the public might become confused, or might think that Hormel endorses Spam Arrest's products.

Seattle attorney Derek Newman, who represents SpamArrest LLC, said: "Inexplicably Hormel is challenging anyone who uses the word spam as part of a trademark.

"Spam has become ubiquitous throughout the world to describe unsolicited commercial email. No company can claim trademark rights on a generic term. SpamArrest is both our corporate name and an arbitrary trademark.

"We are not claiming the right to use the generic term spam alone, but we will protect the name of our of our company and the brand of our product."

The row centres on two trademark applications filed by SpamArrest LLC in early 2002 for the term Spam Arrest.

It was granted a trademark (in international class 009) for "computer software, namely, software designed to eliminate unsolicited commercial electronic mail".

This trademark was challenged last week by Hormel. A second application by SpamArrest for a trademark (in international class 042) for online computer services was challenged before it was granted.

The cases are pending before the trademark trial and appeal noard, according to the website of the US Patent and Trademark Office.

SPAM products began to appear on the shelves of US grocery stores in 1937, and last year Hormel marked the sale of the six billionth can. The Spam range includes Spam, Spam Oven Roasted Turkey, Spam Smoke Flavored, Spam Lite or Spam Less Sodium.

Hormel could not be reached for comment at the time of publication.