VoiceXML::Client is a library that provides Perl programs with the ability to act as a user agent that fetches Voice Extensible Markup Language (VoiceXML) documents, parses them, and then executes the instructions therein by playing prompts and collecting user DTMF input/voice recordings through a handle to some type of telephone or other device interface. VoiceXML::Client's focus is on the client side. The XML documents are generated by a distinct process of your choice, unrelated to the library.
PHP Voice (formerly known as PHP VXML) contain four classes that assist in developing voice application using PHP. It supports Speech Synthesis Markup Language 1.0, Speech Recognition Grammar Specification 1.0, Voice Browser Call Control: CCXML 1.0, and Voice Extensible Markup Language (VoiceXML) 2.0.