I gave up on that and wrote a simple i2c (master-only) library instead.
However I have only been able to tweak Wire 0011 library to be a reliable I2C Master<>Slave network. Wire 0012 and 0013 works for about 100 byes then freezes. I have spent several hours trying to determine why, but have yet to find a tweak that will make I2C reliable.
Are you using the OSX version the IDE? If so then there's a "known" bug with the avr-gcc compiler (4.3) that's included with Arduino 0012 and 0013. The compiler generated bad interrupt handling code which causes crashes and lockups. The Wire library relies on interrupts so your freezes match how this bug manifests.