How to install module tablefunc

Hello,<br /><br /> I'm currently running on linux and with pgSQL8.4.<br /> I would like to use the crosstab function
avalablein the tablefunc module.<br /> Unfortunately I don't know where to download/install this module.<br /><br />
Anyhelp??<br /><br /> Best regards<br /><br /><table cellpadding="0" cellspacing="0" width="100%"><tr><td><font
size="4">-----</font><br/><img align="top" border="0" src="cid:1264930493.25399.83.camel@Dell_Inspiron" width="100"
/><br/><b><font color="#000080">Florent THOMAS</font></b><br /> 11, rue du petit Saint Christophe<br /> Résidence
Dauderde Selva - Bât2<br /> 66000 Perpignan<br /> 06 16 73 40 18<br /><a
href="mailto:florent.thomas@tdeo.fr">florent.thomas@tdeo.fr</a><br/><a href="http://www.tdeo.fr">www.tdeo.fr</a><br
/><ahref="http://www.kipigo.com">www.kipigo.com</a> <b><font color="#ff0000">Nouveau!</font></b><br /><br /><br
/></td></tr></table><br/>