Despite efforts of businesses to educate Americans about the need to plan wisely for retirement, too many workers are making common mistakes - not saving enough, for example, or relying too heavily on company stock.

Self-employed individuals or those who own a business that employs only their spouse are not taking advantage of Individual 401(k)s, thinking that they can't afford to set up a retirement plan, according to Fiducial, an international financial services firm.

"The hottest thing for self-employed individuals or a very small company's business owner and spouse is the Individual 401(k)," said Wm. Leon Carter, a registered investment adviser for Fiducial in Stark, Ore. "They are fairly new products and give the participants the ability to make loans on contributions to a 401(k) unlike regular retirement plans such as a Simplified Employee Pension Plan (SEP)."

It costs just $750 to set up a plan and about $50 per employee per year to maintain it, Carter said. Individuals can put 20 percent of their net earnings into the Individual 401(k) fund after self-employment deduction, up to a maximum of $41,000 plus elective deferrals of $14,000 for those under age 50 and $18,000 for those above that age.

A new study by Hewitt Associates shows that more workers - about 70.3 percent - contributed to 401(k) plans last year, up from 69.8 percent in 2003. Still, many workers invested too heavily in their own company's stock.

This despite a public debate over the need for private retirement savings and news reports of workers losing their retirement nest egg when their companies collapsed amid scandal, Lori Lucas, director of participant research at Hewitt, told The News-Press of Fort Myers, Fla.

Lucas said 10 percent to 20 percent is the maximum anyone should hold of any asset, including company stock. The study said that more than one in four workers held half or more of their total 401(k) balances in employer stock.

Jim Applegate, a certified financial planner in Fort Myers, Fla., who sees mostly retired clients, said “sentimental attachment” causes some to hold on to their company stock. "I have seen where (company stock) is 30, 40, 60 percent of a client's investment portfolio," he told the News-Press.

"They say, 'That stock has been good to me.' I tell them it's really nice, but that stock doesn't know you from Adam." He reminds them "of Enron and the land mine a single stock in their portfolio can be."

Another common mistake is not choosing consultants carefully. The Securities and Exchange Commission on Monday released a study that said pension consultants, chosen by companies to help pick mutual funds and other investments for 401(k)s, may not be revealing conflicts of interest. Consultants may be swayed by payments from money managers. More than half of the consultants provided services to pension funds and money management firms, the study said.

"Individual investors have the right to expect that those professionals handling their money do so in a way that's unbiased and objective," Lori Richards of the SEC's examinations division, told USA Today.