WebEx Communications ( WEBX) was higher after the Internet-service provider said fourth-quarter earnings were up 40% from a year ago on a per-share basis, to $21.8 million, or 42 cents a share, excluding items. Revenue climbed 22% to $101.9 million. Analysts were seeking a profit of 38 cents a share on sales of $101.4 million. Looking ahead, the Santa Clara, Calif., company expects 2007 earnings to range between $1.60 and $1.70 a share on a non-GAAP basis, and sales should be between $450 million and $465 million. The Street is calling for $1.62 a share on $454.1 million in revenue. Shares were gaining $2.42, or 6.5%, to $39.50. Shares of Tractor Supply ( TSCO) dropped after the Tennessee-based conglomerate issued 2007 earnings guidance of $2.45 to $2.52 a share, which is at least 9 cents below Wall Street expectations. Revenue should be between $2.7 billion and $2.74 billion, roughly in line with estimates, and the farm-products retailer projects a 3% to 4% same-store sales increase. For the fourth quarter, Tractor Supply reported a profit of $29.5 million, or 72 cents a share, on revenue of $629.9 million. Income beat Street estimates by a penny, but sales just missed the $633.6 million estimate. Shares were losing $2.33, or 4.6%, to $48. Boston Properties ( BXP) shares were lower after the real estate investment trust said it's offering $750 million in exchangeable senior notes, with an additional $112.5 million option for the initial purchasers to cover any overallotments. Shares were down $5.09, or 4%, to $121.