PHP Fatal error: Call to undefined function: money_format()

I have php 4.3.2 and I am getting this error. Any explinations?
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Manual Page -- [url]http://www.php.net/manual/en/function.money-format.php[/url]
Edit Note -- [url]http://master.php.net/manage/user-notes.php?action=edit+33945[/url]
Delete Note -- [url]http://master.php.net/manage/user-notes.php?action=delete+33945&report=yes[/url]
Reject Note -- [url]http://master.php.net/manage/user-notes.php?action=reject+33945&report=yes[/url]