Hint:

Important Note

Arduino v1.0.1 (and maybe newer) have a malloc/free bug!

Check:

• http://code.google.com/p/arduino/issues/detail?id=468
• http://code.google.com/p/arduino/issues/detail?id=857

Howto fix this issue:

• go to issue #468
• download malloc.c
• copy malloc.c to arduino-1.0.1/hardware/arduino/cores/arduino

Restart the Arduino IDE!