jenkinsci/git-client-plugin — pull request #130 by steven-collins-omega (2014-04-23 19:32:46+00:00)
Title: [FIXED JENKINS-20941] Use credentials for "submodule add" and "submodule update"

I don't necessarily expect this pull request to be accepted as-is, as I didn't add any tests, and I don't have time to do so currently. It does seem to work, though, and doesn't break any existing submodule tests.