I installed the latest version of the plugin.
I then attempted to configure it to handle the most simple case possible; generating a CHANGELOG.txt file based on the difference between $GIT_PREVIOUS_COMMIT and $GIT_COMMIT

I get this error. Here is the console log:

Checking out Revision 67e061dcfa6c9edf6fce28c40939418a0c334ea3 (origin/foo)
> git config core.sparsecheckout # timeout=10
> git checkout -f 67e061dcfa6c9edf6fce28c40939418a0c334ea3
> git rev-list 67e061dcfa6c9edf6fce28c40939418a0c334ea3 # timeout=10
[workspace] $ /bin/sh -xe /tmp/hudson770153796434746119.sh
+ echo GIT_COMMIT is 67e061dcfa6c9edf6fce28c40939418a0c334ea3
GIT_COMMIT is 67e061dcfa6c9edf6fce28c40939418a0c334ea3
+ echo GIT_PREVIOUS_COMMIT is 67e061dcfa6c9edf6fce28c40939418a0c334ea3
GIT_PREVIOUS_COMMIT is 67e061dcfa6c9edf6fce28c40939418a0c334ea3
+ echo GIT_PREVIOUS_SUCCESSFUL_COMMIT is 67e061dcfa6c9edf6fce28c40939418a0c334ea3
GIT_PREVIOUS_SUCCESSFUL_COMMIT is 67e061dcfa6c9edf6fce28c40939418a0c334ea3

+ exit 0
—
--- Git Changelog —
---
Creating changelog CHANGELOG.txtInvalid id: 67e061dcfa6c9edf6fce28c40939418a0c334ea3