Sunnyvale, Calif.--eGain Communications said Thursday that it plans a $78.6 million merger with Inference Corp. in a bid to give the combined entity clout in the burgeoning customer relationship management (CRM) market. If approved by shareholders, the move would join eGain's software for managing incoming customer inquiries from the Web, call centers, sales forces and direct mail with Inference's software and services for making Web customer service effective. Inference, San Francisco, and eGain, Sunnyvale, Calif., are under increasing pressure to grow and expand services because market leaders such as Siebel Systems Inc. and E.piphany are building complete end-to-end CRM packages. Historically, companies have relied on individual applications, which address only one or two specific customer relationship needs. International Data Corp. said corporate spending on global customer care software will double to $58.6 billion by 2003 in call centers, while similar purchases for Internet systems will reach $14 billion.