space b/w glyph in true type font is not proper

Hi,

If I use php build of gd, space b/w characters of string is proper.
However, when I use gd C library, the space is not proper.

PHP code:
------------------------------------------
<?php
$im = imagecreatetruecolor(100,100);
 $white = imagecolorallocate($im, 255, 255, 255);
 $grey = imagecolorallocate($im, 128, 128, 128);
 $black = imagecolorallocate($im, 0, 0, 0);
 imagefilledrectangle($im, 0, 0, 100, 100, $white);

 $text = 'Yahoo';
 $font = '/tmp/arial.ttf';

 imagettftext($im, 8, 0, 10, 10, $black, $font, $text);

 imagepng($im,"/tmp/test.png");
 imagedestroy($im);
 ?>
------------------------------------------

C code:
------------------------------------------
#include <gd.h>
#include <stdio.h>
#include <fstream>
#include <gdfonts.h>

//g++ code.cc -I/usr/local/include -lgd  -L/usr/local/lib


int main(int argc, char *argv[]) {
    gdImagePtr im = gdImageCreateTrueColor(100,100);
    int white = gdImageColorResolve(im, 255, 255, 255);
    int black = gdImageColorResolve(im, 0, 0, 0);
    gdImageFilledRectangle(im,0,0,100,100,white);

    gdImageStringFT(im,NULL,black,"./arial.ttf",8,0.0,10,10,"Yahoo");

    FILE *pngout = fopen("test.png", "wb");
    gdImagePng(im, pngout);
    fclose(pngout);
    gdImageDestroy(im);
}
------------------------------------------

C library version used: gd-2.0.36_2,1
PHP info:
Array
(
    [GD Version] => bundled (2.0.34 compatible)
    [FreeType Support] => 1
    [FreeType Linkage] => with freetype
    [T1Lib Support] => 1
    [GIF Read Support] => 1
    [GIF Create Support] => 1
    [JPG Support] => 1
    [PNG Support] => 1
    [WBMP Support] => 1
    [XPM Support] =>
    [XBM Support] => 1
    [JIS-mapped Japanese Font Support] =>
)


Attaching the images for php & C library also.
What I am missing here?

Regards
Prashant