Updated from 7:55 a.m. EDTSiebel Systems ( SEBL) shares tumbled Thursday after the company warned late Wednesday that second-quarter results would fall far short of analyst estimates. The company cited delays in purchasing decisions, an explanation that has been repeated by numerous software companies during this painful preannouncement season. In recent trading, Siebel shares were down $1.07, or 11.6%, to $8.14. San Mateo, Calif.-based Siebel, which makes customer-relationship management (CRM) software, said it expects total second-quarter revenue to total $301 million -- far short of the $353.1 million consensus estimate gathered by Thomson First Call. The company said license revenue -- a key benchmark of new sales -- totaled $95 million. That's the lowest level for license revenue since March 1999, according to Piper Jaffray analyst Tad Piper. "Overall, we remain a cautious stance on Siebel as competition in the CRM space continues to heat up and Siebel's market share may be deteriorating in key segments of the CRM market," Piper wrote in a note Thursday. Piper, who maintained his market perform rating on Siebel, was among a number of analysts who lowered estimates following the company's miss. (Piper Jaffray hasn't done banking with Siebel.) In the wake of the warning, Pacific Growth Equities analyst Pat Mason downgraded Siebel to equal weight from over weight and significantly reduced his EPS and revenue estimates for fiscal years 2004 and 2005. "With deal sizes shrinking and sales cycles lengthening for a company that depends on high average selling prices , at this time we feel visibility for growth is limited," Mason wrote. (Pacific Growth has not done investment banking for Siebel but does make a market in the stock.) In a conference call late Wednesday, Siebel CFO Ken Goldman also said earnings should fall below the company's guided range of 5 cents to 7 cents a share, including a penny a share dilution from Siebel's recent acquisition of banking systems company Eontec. The consensus estimate fell at the high end of that range, at 7 cents a share.