Updated from 12:39 p.m. EDTThe tech sector suffered through another round of warnings Friday, but it also got a shot of good news -- from overseas. Shares of German business software giant SAP ( SAP) rose Friday after the company raised second-quarter sales estimates. SAP expects to report sales of $2.2 billion and operating income of $520 million to $532 million. Analysts had expected SAP to report sales of $2.17 billion. The news spurred an enthusiastic response from investors weighed down by warnings this week from sector heavyweights PeopleSoft ( PSFT) and Siebel ( SEBL). Shares of SAP traded up $2.08, or 5.5%, to $40.04. Elsewhere, though, the news was decidedly mixed. Unisys ( UIS) was among the worst-performing technology stocks after the technology services company warned that second-quarter earnings and sales would fall short of previous expectations. Deferrals of enterprise server contracts and delays of service projects late in the quarter led to the earnings and sales shortfalls. Unisys now expects to report a pro forma profit of 10 cents to 11 cents a share on sales of $1.38 billion to $1.39 billion. Previously, it expected to earn 14 cents to 17 cents. Analysts polled by Thomson First Call expected it to earn 12 cents a share on sales of 1.51 billion. Shares of Unisys traded down $1.99, or 15.5%, to $10.87. SCM Microsystems ( SCMM) fell after it posted weak sales for the second quarter. Sales of $11.5 million were significantly below the $13 million to $15 million the company had projected. It also intends to write down $2.5 million to $3 million for inventory that it doubts it can sell. Shares of SCM Microsystems traded down 96 cents, or 16.1%, to $4.99. On the plus side, StorageTek's ( STK) stock buyback plans trumped a late Thursday sales warning. The storage networking concern warned that it would earn 29 cents to 33 cents a share, about a penny shy of the consensus estimate, on second-quarter sales of $510 million to $520 million. Analysts had expected sales of $549.4 million. But the company upped its stock repurchase plan to $500 million, citing its confidence in its prospects. Shares jumped $3.05, or 12.1%, to $28.30. Shares of Metron Technology ( MTCH) vaulted after the company reported a narrower-than-expected fourth-quarter loss of 1 cent a share on sales of $62.2 million. Excluding items, the company would have reported a fourth-quarter profit of 5 cents a share. Analysts had expected it to report a loss of 8 cents a share on sales of $61.3 million. Looking ahead, Metron expects to report a pro forma first-quarter profit of 3 cents to 5 cents a share. Analysts are expecting it to earn 3 cents a share. Shares of Metron Technology traded up 40 cents, or 16.9%, to $2.77. Other technology volume leaders included Microsoft ( MSFT), up 22 cents to $27.86; Oracle ( ORCL), up 11 cents to $11.03; Intel ( INTC), up 35 cents to $26.57; Sirius Satellite Radio ( SIRI), up 1 cent to $2.79; Cisco ( CSCO), up 19 cents to $22.36; Yahoo! ( YHOO), up 3 cents to $30.11; Lucent ( LU), unchanged at $3.46; and Nortel Networks ( NT), up 2 cents to $4.37.