Hi,
apologize for using the Core Server Project, but couldn't find anything more suitable. However, since the 2.4.x release, the 2.2.x version is not available from the official 10gen repositories for Rhel / Centos.

yum list mongo

Installed Packages
mongo-10gen.x86_64 2.2.0-mongodb_1 @10gen
mongo-10gen-server.x86_64 2.2.0-mongodb_1 @10gen
Available Packages
mongo-10gen.x86_64 2.4.1-mongodb_1 10gen
mongo-10gen-server.x86_64 2.4.1-mongodb_1 10gen
mongo-10gen-unstable.x86_64 2.1.0-mongodb_1 10gen
mongo-10gen-unstable-server.x86_64 2.1.0-mongodb_1 10gen
mongo18-10gen.x86_64 1.8.5-mongodb_1 10gen
mongo18-10gen-server.x86_64 1.8.5-mongodb_1 10gen
mongo20-10gen.x86_64 2.0.8-mongodb_1 10gen
mongo20-10gen-server.x86_64 2.0.8-mongodb_1 10gen