Wall Street can be quite demanding. Although VeriSign (NASDAQ:VRSN) exceeded the analysts' consensus forecasts for the fourth quarter, it disappointed on its own outlook.

VeriSign is a key Internet infrastructure company, focusing on cell phone ringtones and secure transactions. But the company could do nothing to protect itself from negative investor sentiment. Yesterday, the stock price tanked 13%, to $25.46.

In the fourth quarter, VeriSign posted quarterly revenues of $356 million, a 41% increase from the same period a year ago. Net income was $115 million, although about $78 million of that amount came from a cashout of VeriSign Japan holdings.

VeriSign's CEO, Stratton Sclavos, claims "significant momentum in existing lines of business." Thus, he calls for 2004 revenues of $1.5 billion to $1.55 billion, with earnings of $0.90 a share. This was an increase from prior guidance of $1.4 billion to $1.42 billion in revenues and earnings per share of $0.84 to $0.85.

But, of course, Wall Street had hopes of better results. And the additional growth was expected to come from VeriSign's wireless-content division, which has been built through several high-priced acquisitions, including Jamba! and LightSurf. These acquisitions add not only key technologies and content but also important alliances. LightSurf, for example, brings such big buddies as Sprint (NYSE:FON), Qwest (NYSE:Q), and Motorola (NYSE:MOT).

This week, investors were expecting very strong results from VeriSign, especially in light of the stock price surge in InfoSpace (NASDAQ:INSP), which reported solid performance in its wireless operations. Why not the same for VeriSign, whose wireless-content sales are poised to tally a third of its revenues this year?

Well, keep in mind that wireless content is still in the early stages. Smooth growth is not to be expected. For example, the wireless content contributed $94 million to revenues in the fourth quarter. Yet Wall Street thought the number would be in excess of $100 million.

This is short-term noise. Mobile applications are becoming much more complex and require sophisticated infrastructure solutions. With smart acquisitions, VeriSign now has that infrastructure.

Fool contributor Tom Taulli does not own shares mentioned in this article.