I blogged back in August about the increasingly fuzzy line between personal and business activities online, noting that Whole Foods CEO John Mackey's anonymous posts on Yahoo financial forums not only embarrassed the company when Mackey was outed but also briefly threatened its acquisition of rival Wild Oats Markets.

Anonymity and aliases on the Internet, while common, are rarely a good idea, wrote IT Business Edge blogger Rob Enderle. For one thing, Internet anonymity is an illusion, thanks to sophisticated tracking software. Enderle writes:

I suggest you assume anything you write can, and will, at some future point be tracked back to you. That way you are more likely to utilize proper judgment and avoid future embarrassment to those you work with and those you care about.

It's good advice, and words that Cisco employee Rick Frenkel may have wished he'd heeded. Two Texas patent attorneys are suing Frenkel and Cisco for defamation, alleging that Frenkel damaged their reputations in anonymous posts he wrote for the Patent Troll Tracker blog, reports News.com.

In recently revealing his identity on the blog, Frenkel mentioned that his immediate supervisor at Cisco had been aware of his blogging activities. This makes not only Frenkel, but Cisco, liable, say the two litigants.

This incident highlights the large and growing gray area of employees who may post personal blog entries about work-related issues. Cisco just added this to its three-year-old Internet postings policy:

If you comment on any aspect of the company's business or any policy issue the company is involved in where you have responsibility for Cisco's engagement, you must clearly identify yourself as a Cisco employee in your postings or blog site(s) and include a disclaimer that the views are your own and not those of Cisco.

Such disclosure is by no means a given in corporate blogging policies, notes News.com. Among the companies that do not address these types of situations in their policies are Google, Yahoo and Sun Microsystems. However, Dell and IBM require employees to reveal their professional affiliation when blogging about topics that relate to company business. Other companies questioned by News.com chose not to share their blogging policies.

You'd think that Frenkel, a lawyer himself, might have more carefully considered the possible ramifications of his posts. Yet oddly, says IT Business Edge's Ken Hardin in commenting on the incident in which blogger Kathy Sierra last year received online threats on her life, "people have come to believe that the Internet is this magical new world where there simply aren't any laws."

While I don't think this is exactly true, there is an alarming dearth of legal precedent online. That seems fated to change, with high-profile lawsuits like the one against Cisco. A good rule of thumb: If something can get you sued offline, then it can probably get you sued online as well. Hardin writes:

Terroristic threatening has always been illegal on the Internet, in a coffee shop, in your mom's dining room -- you name it. Same with copyright protections and libel laws.

Yet bloggers tend to chafe at the idea of any kind of corporate control over their activities. A dozen large companies, including Coca-Cola Co., Wells Fargo, General Motors and Dell, got slammed in the blogosphere late last year after creating a Blog Council to create and promote best practices for corporate blogging.

In another interesting case, the anonymous author of a blog titled Civil Serf has reportedlybeen suspended from her job at the UK's Department for Work and Pensions after she confessed her activities to a government investigative team., reports out-law.com. It's not clear whether she violated the UK's civil service code of conduct with her blogging.

Employment law specialist Catherine Barker tells out-law.com:

Employers need to ensure that the ground rules of acceptable behaviour online are firmly established. This is particularly true where an employee is posting information in cyberspace in his or her own free time, using their own computer equipment, rather than that belonging to his or her employer.