library function printf in case of st10f272z2

I've recently upgraded from an ST10F168 to ST10F272
I made a fresh project and in that with the following settings i can use library functions putchar , and puts
But I can not use "printf", if I use printf then only first character gets displayed on the hyper terminal.
my settings are as follows
H/ W settings
crystal = 4Mhz
P0H.7,6,5 = 1,0,0 ..resp. so my CPU freq = 20 Mhz
my code is as follows
#include <reg167.h>
#include <stdio.h>
#include <intrins.h>

void serial_setup (unsigned int baud)
{ S0BG = (20000000 / (32*(unsigned long) baud)) - 1; /* baudrate reload */ DP3 |= 0x0400; /* Set TXD for output */ DP3 &= ~0x0800; /* Set RXD for input */ P3 |= 0x0400; /* Set TXD high */
// tx_restart = 1; /* Set restart flag */ S0CON = 0x8011; S0RIC = 0x0044; /* Enable serial receive interrupt level 1 */ S0TIC = 0x0080; /* Enable serial transmit interrupt level 2*/
}

void main (void)
{ serial_setup (19200);

IEN = 1; /* Enable interrupts */ puts("i am here"); printf("Serial I/O Initialized\n"); while (1) { char c; c = getchar (); }
}