Sunnyvale-based Untangle, which develops firewall and Internet management appliances, said Thursday that it has acquired eSoft, a developer of an integrated firewall, email and web threat security appliance. Financial terms of the buy were not announced by the companies. Untangle said the buy was structured as an asset purchase, and that it acquired eSoft's domain name, firewall technology and appliances, and existing customer contracts. Untangle will as hire on some of eSoft's employees to suppor customers and partners. eSoft was based in Broomfield, Colorado.