How can I add private information to OpenShift environment variables?

Authentication information such as database connection strings or passwords should almost never be stored in version control systems.

It looks like the only method of specifying environment variables for an app hosted on OpenShift is to commit them to the Git repository. There is a discussion about this on the OpenShift forums, but no useful suggested workarounds for the problem.

Is there another approach I can use to add authentication information to my app without having to commit it to the repository?