Installing testing packages with yum

[Jorge Castelao <jorge@xxxxxxxxxxxxx>]

I want to install the testing package gimp-1.3.21, which is in the
testing directory of fedora.us

I have in my /etc/yum.conf the line:
baseurl=http://download.fedora.us/fedora/fedora/$releasever/$basearch/yum/testing

But when I run 'yum install gimp' or 'yum update gimp' I have the
message 'gimp is installed and is the latest version' (the version I
have installed is 1.2.5-1

What am I doing wrong?

Thanks.