GrenHills Multi2000 users

I have read the manuals back and forth and I cannot find any information how can I replace original putchar function with mine - to be able to use printf on my hardware. It always links original library with GHS's putchar routine redirecting I/O to the I/O window in the debugger...I am using version 3.5 for MC68K/Coldfire, although this is basic question independent of the target processor. On KEIL it was as simple as writing my own putchar function and linker will use it before looking into system library. But not in GHS tools :(

- Dejan