The business case for putting mobile e-mail into the hands of more employees gets easier to make as smartphone prices decline. It also helps that IT tools for managing mobile e-mail across companies keep improving. The challenge now: getting the people who need mobile e-mail and those who manage it on the same page.

"There's not a whole lot of people in our company clamoring for it, partly because they don't know how good it is," says Jackie Barretta, CIO for trucking company Con-way. "They don't know to ask for it."

Analyst Sara Radicati estimates that only 5% of the U.S. workforce has mobile e-mail provided by their companies. Employee demand hasn't been strong enough to force companies to deploy mobile e-mail more widely. "I don't think we're anywhere near saturation or near the point of not enough need or want out there," says Scott Cooper, VP of mobility solutions with Nokia's enterprise solutions division.

Ask IT managers why they haven't deployed mobile e-mail more widely, and some will say that on-the-go managers and salespeople have it and that others don't need it. "Almost everybody in our field organization and almost all our execs have mobile e-mail," says Stephen Brobst, CTO of Teradata. "The engineers and the back-office people don't need it because they're normally at a desk with easy access to desktop e-mail."

The situation is similar at Con-way. "Most of the people who don't have it tend to stay in one location all day," says CIO Barretta.

Probe deeper, however, and you may come to the conclusion that a broader range of employees would be more productive if equipped with mobile e-mail devices such as Research In Motion's BlackBerry. Indeed, many employees would want them if they had a clearer idea of the benefits, which include increased flexibility and productivity.

The mobile e-mail industry has a marketing challenge: convincing companies that it's time to push mobile e-mail beyond the executive suite and the field sales force. The good news is that the obstacles are lowering, in part because more employees are taking it upon themselves to work this way. As with technologies like social networking, mobile e-mail for the masses is being driven less by corporate decision-makers and more by the rank and file.

"It's not purely a corporate dimension driving adoption," says Nokia's Cooper. "Whether IT is pushing it or not isn't the key variable in this equation. It's more people using it outside the office and wanting to bring it inside."