Updated from 12:53 p.m. EDT Shares of Sonus Networks ( SONSE) were among the best-performing technology stocks Tuesday after the company completed an internal investigation and said it would restate financial results for 2001, 2002, and the first three quarters of 2003 in connection with the review. While the company did not disclose the terms of the restatement, it did say the primary effect would be the "timing of revenue recognition and certain other financial statement accounts." It also said it expects to file an amended annual report for 2003 and its 2004 first-quarter report with the Securities and Exchange Commission within a week. What's more, it requested additional time from the Nasdaq Stock Market so that it can regain compliance with filing requirements. Shares of Sonus Networks traded up 73 cents, or 17.8%, to $4.83. SS&C Technologies ( SSNC) rose after it reported stronger-than-expected second-quarter earnings and upped third-quarter guidance. Second-quarter earnings of 21 cents a share were better than the 19 cents that analysts polled by Thomson First Call had expected. Sales of $24.5 million were ahead of expectations as well. Looking ahead, it expects to earn 19 cents to 20 cents a share on sales of $24.5 million to $25 million. Analysts were expecting it to earn 18 cents a share on sales of $23.9 million. Shares of SS&C Technologies traded up $3.41, or 20.2%, to $20.26. Shares of Supertex ( SUPX) rose after the mixed-signal semiconductor manufacturer reported better-than-expected first-quarter earnings. It earned 14 cents a share on sales of $14.2 million. An analyst following the company had expected it to earn 7 cents a share. A favorable product mix, lower depreciation expenses, and stringent cost-reduction measures contributed to the strong first-quarter results. Shares of Supertex traded up $3.59, or 25.6%, to $17.59.