Max Firmata is Firmata Client for Max/MSP. Max Firmata supports most of features of Firmata protocol. Up to 4 software and 4 hardware UART, 1 I2C, 5 Encoder, 6 Stepper. Also Servos, Digital and Analog IO, PWM Output and so.
@MP there is a mxf file for windows x64. If you have different version (Mac OS X or Win x86) you can create mxf file. Open source/maxfirmata25.maxpat - press file/build collective and save mxf file. It's included everything in source dir on one file. If you build Mac or Win x86 mxf file please send mxf file to me. I can add it to github page :)