Description:
------------
if fdf_set_value is set with a string of 255 characters nothing is returned when using fdf_get_value

Test script:
---------------
<?

$outfdf = fdf_create();

$value = 'PAINT (including paint, lacquer, enamel, stain, shellac, varnish, polish, liquid filler and liquid lacquer base) with not more than 20 per cent nitrocellulose by mass if the nitrogen content of the nitrocellulose is not more than 12.6 per cent by mass; or';
fdf_set_value($outfdf, 'Stringof255characters', $value, 0);
print "Test1: ";
print fdf_get_value($outfdf, 'Stringof255characters'); //prints ''

print "<br>";

$value = substr($value,0,253);
fdf_set_value($outfdf, 'Stringof253characters', $value, 0);
print "Test2: ";
print fdf_get_value($outfdf, 'Stringof253characters'); //prints the 253 characters of the string

?>

Expected result:
----------------
both print fdf_get_value should print the value of the string

Actual result:
--------------
if fdf_set_value is set with a string of 255 characters nothing is returned when using fdf_get_value