[CentOS] CentOS6: installing 32bit and 64bit RPMS via the installer?

Installing 64bit CentOS6 only installs x86_64 and noarch RPMS - however, 
I have a number of legacy 32bit apps that require a number of 32bit RPMS 
to be installed.

Does anyone know how to get the installer to install the 32bit versions 
of 64bit RPMS? i.e. in the way it does for CentOS5.

Thanks

James Pearson