Denver, Colorado-based Jabber has expanded its executive team, saying this morning that the firm has added a new VP of Sales and Support, and a General Manager for its government sales. Jabber said that it has named Denise M. Fields as new VP of Sales and Support Services, and Harry B. Heisler as VM of Jabber Government. Fields was most recently at Davinci Associates, the entrepreneurial incubator in Boulder. Heisler was most recently at Ezenia Government Systems, a technology solutions proivder to the intelligence community. Heisler has also served at MicronPC Government Systems. Jabber is developing software used for instant messaging systems.