Hello Sergyi,
I've just tried my Wacom intuos pen with both the eraser and the pen appear to working fine. I set the mode to "Firm" on the tablet and checked the pressure sensitivity on the model and it worked for me.
Mac OSX 10.5.4
2 X 2.8 GHz Quad-Core Intel Xen
2 GB 800 MHz DDR@ FB-DIMM
NVIDIA GeForce 8800 GT
Hope this helps!