Install * with res_jabber, chan_gtalk on CentOS

I want to make calls using Google Talk. I installed Asterisk on my CentOS 5.7 machine using yum. But I don’t have either chan_gtalk or res_jabber in /usr/lib/asterisk/modules. Here are the packages I have installed:

#yum list installed | grep asterisk asterisk.x86_64 installed asterisk-configs.x86_64 installed asterisk-core.x86_64 installed asterisk-dahdi.x86_64 installed asterisk-doc.x86_64 installed asterisk-sounds-core-en-gsm.noarch 1.4.21-1_centos5 installed asterisk-voicemail.x86_64 installed asterisk18-addons.x86_64 installed asterisk18-addons-bluetooth.x86_64 installed asterisk18-addons-core.x86_64 installed asterisk18-addons-mysql.x86_64 installed asterisk18-addons-ooh323.x86_64 installed asterisknow-version.noarch 1.7.1-3_centos5 installed
Is chan_gtalk and res_jabber in a different package?