natri64:
what can I do?
I don't know 
It might not be the just the Wire library, it might also be the I2C hardware of the Arduino.
If a byte is received, it is read in a interrupt routine and that probably holds the I2C bus while the interrupt routine is busy. I think there is no way to change that.
You could use a PCA85132, and connect the output wires (the lcd wires) to an Arduino and convert that into text.
Perhaps the software pin-toggle of the MB91F248 has been tuned for the PCA85132 to make that chip work and they didn't care about I2C compatibility.