buddy, even if u are using a linux platform, you must be having windows, rite? So why not make Sam speak, then record the voices in wav or mp3 format with the sound recorder or any other third party recording software, and then use those files in Linux?? Its tht simple..
Go here .register and then use demo to generate wave files 1 to 10 .
This is one of the best text to speech softwares available Nuance - RealSpeak - Demo