/media/sandbox/xtools/avr-dev/build/avr/bin/avr-gcc -g -Wall -O2 -mmcu=at90s4433    -c -o main.o main.c
In file included from main.c:20:
/media/sandbox/xtools/avr-dev/build/avr/lib/gcc/avr/3.4.4/../../../../avr/include/avr/signal.h:36:2: warning: #warning "This header file is obsolete.  Use <avr/interrupt.h>."
main.c: In function `ioinit':
main.c:104: warning: implicit declaration of function `timer_enable_int'
/media/sandbox/xtools/avr-dev/build/avr/bin/avr-gcc -g -Wall -O2 -mmcu=at90s4433  -Wl,-Map,main.map -o main.elf main.o 
main.o: In function `ioinit':
/media/sandbox/xtools/avr-dev/build/test.all/at90s4433/demo/main.c:104: undefined reference to `timer_enable_int'
make: *** [main.elf] Error 1