inVue[Janaka C.Paranamanage]- inVue is a CRM application and the company is headquartered in the UK. We have being using James for the past 12 months. It is a stable and very useful mail server for us.
JSender- JSender is a permission based email marketing system in Hong Kong. We are using James for our daily email delivery. It is Java based and fit our infrastructure very well.
Center for Life Resources - Center for Life Resources is a behavioral healthcare system in the state of Texas, serving 7 counties. We were drawn to James due to the low memory footprint and scalable/modularized nature. The Apache License didn't hurt matters either!