SAP ( SAP), which had looked unstoppable for much of the year, stumbled in the second quarter, sparking fears that IT spending may be slowing.

The unexpected miss provoked a selloff of SAP shares; in recent trading the stock was off $3.19, or 6.3%, to $47.15. Most software issues were down as well, though the bulk of those losses were much smaller.

Despite the poor second quarter, the company reaffirmed guidance for the rest of the year. CEO Henning Kagermann said the miss does not signal an industry-wide slowdown, and said on a conference call that a number of deals that were expected to close at the end of the quarter slipped. "The good news is we have not lost deals, the order entry is extremely strong and the pipeline is strong, so that's why we could reaffirm our guidance," he said on a conference call after the announcement.

The major culprit in the second-quarter miss, announced a week before final results will be released, was weaker-than-expected sales of new software licenses. The company said those sales rose 8% to 621 million euros ($790 million), missing all estimates in a Reuters poll of 24 analysts, whose forecasts averaged 675 million euros.

Not only did the company miss on licenses, Kagermann admitted that SAP lost share to "our peer group," meaning Microsoft ( MSFT) and Oracle ( ORCL).

Although Kagermann said the loss of share to the two software giants was small, and that SAP actually gained share vs. the total market, it was still an important psychological victory for Oracle, which is locked in a serious struggle with SAP to dominate the market for enterprise business applications.

SAP's sales of software licenses in the U.S. were strong, increasing by 16% year over year, while Europe, SAP's biggest market, grew by a sluggish 3%.

Commenting on the miss, ICAP chief software analyst Richard Williams wrote: "SAP missed by 8.54% in licenses in 2Q, which is a surprisingly large miss, especially for such a juggernaut of a software player. The comments from many different sources recently explaining that deals slipped or customers deferred signings left us with chills. The eerie resemblance with prior periods of major blowups is just too similar for comfort."

Goldman Sachs analyst Rick Sherlund called the license miss "disappointing," but was much less pessimistic than Williams. "This is likely more of a bump in the road vs. any real change in fundamentals. We believe the overall health of the enterprise applications markets remains favorable, with Oracle reporting strong growth in applications and SAP reiterating expectations for 15%-17% license growth for the full year," he said in a note to clients.

Sherlund also said that the company's pro forma EPS of 1.41 euros beat his estimate of 1.17 euros, "as it appears the company was able to more than offset weaker license revenue with lower costs."

Goldman Sachs has an investment banking relationship with SAP; ICAP does not.

Revenue for the 2006 second quarter is expected to be approximately 2.20 billion euros ($2.78 billion), which represents an increase of 9% compared to the 2005 second quarter, the company said.