Siebel Systems ( SEBL) was among the worst-performing technology stocks Thursday after the business applications software company warned that second-quarter sales would fall well short of expectations. Delays in customer purchasing plans contributed to the sales shortfall. Siebel now expects pro forma operating income of $8 million to $10 million on sales of $301 million. Analysts polled by Thomson First Call had expected it to report sales of $353.1 million on earnings of 7 cents a share. Shares of Siebel Systems traded down $1.23, or 13.4%, to $7.98. Shares of eLoyalty ( ELOY) rose after the company raised its second-quarter revenue estimates. The company's service revenue is now expected to be between $16.1 million and $16.4 million vs. its previous guidance of between $14 million and $15.5 million. Total revenue for the second quarter is now expected to be $17.9 million to $18.2 million. The upward revision in service revenue was due to better-than-expected performance in new and existing accounts. Shares of eLoyalty traded up 50 cents, or 7.8%, to $6.90. CheckFree ( CKFR) rose after it signed a five-year contract extension to provide electronic billing and payment services to Wachovia ( WB). CheckFree now serves a portion of Wachovia's online bill payment customers, but eventually Wachovia will migrate all of its retail and small-business customers to the CheckFree platform. Shares of CheckFree traded up $2.35, or 8.2%, to $30.81. Shares of BMC Software ( BMC) fell after the company lowered first-quarter earnings and sales guidance. Excluding items, it now expects to report earnings of 11 cents to 14 cents a share on sales of $318 million to $328 million. In April, the company said it would earn 12 cents to 16 cents a share on sales of $345 million to $355 million. Analysts had expected it to earn 13 cents a share on sales of $351 million. Delayed customer purchasing decisions, particularly by U.S. customers, led the company to revise its financial outlook. Its shares traded down $2.51, or 15.1%, to $14.16. OpenTV ( OPTV) rose after it settled a patent suit with Disney ( DIS) and agreed to grant Disney and its ESPN and ABC subsidiaries a nonexclusive, royalty-bearing license to use its patents. The patents will allow Disney to use the Internet to supplement its television broadcasts. The companies have also entered into negotiations for a multiyear development agreement whereby OpenTV would provide Internet content for use on Disney's television programming. Shares of OpenTV traded up 50 cents, or 26.7%, to $2.37. Other technology volume leaders included Yahoo! ( YHOO), down $2.52 to $30.08; Oracle ( ORCL), down 28 cents to $10.92; Microsoft ( MSFT), down 46 cents to $27.64; Intel ( INTC), down 12 cents to $26.22; Cisco ( CSCO), down 25 cents to $22.17; Sun Microsystems ( SUNW), down 4 cents to $4; Lucent ( LU), down 3 cents to $3.46; and Nortel Networks ( NT), down 25 cents to $4.35.