Palo Alto-based virtualization software provider VMware said today that it has entered into a definitive agreement to acquire Thinstall, a San Francisco-based provider of application virtualization software. Financial terms of the acquisition were not disclosed. According to VMware, it is acquiring Thinstall to expand its desktop virtualization capabilities. Thinstall was founded in 1999. VMware also said it has acquire the services-related assets of Foedus, a New Hampshire-based provider of virtualization technologies and services. VMware said that acquisition will help it to expand its virtualization services business.