We propose and implement a low-cost Thai voice gateway that combines current technology in network systems and telephony. It enhances traditional telephony-based applications with access to resources on the Web. The system is based on open standards for speech technology and existing open source software. It supports the VoiceXML markup language for voice dialogs, the MRCP protocol for communication with a speech engine provider, and effectively recognizes and synthesizes Thai speech. The system uses a client/server architecture separated into 3 main modules: the VoiceXML interpreter, the speech engine interface, and the telephone integration system. The current prototype still needs improvement but is functional enough to provide a basis for future enhancement. We have released the system as open source software for interested developers.