(PHP 5 <= 5.3.0, PECL ming SVN)
SWFTextField::setLineSpacing — Sets the line spacing of the text field
$height
   )This function is EXPERIMENTAL. The behaviour of this function, its name, and surrounding documentation may change without notice in a future release of PHP. This function should be used at your own risk.
   swftextfield::setlinespacing() sets the line spacing
   of the text field to the height of height. Default is 40. 
  
No value is returned.