Is there a way to change the commit message displayed on a build?

We use parameterized builds to run separate regression and acceptance tests at regular intervals. In our list of builds, these always repeat the commit message, e.g., we’ll have three builds (CI, full regression, acceptance) all with the same commit message (‘Merge pull request #123 from …’). Is there a way to change that commit message, through the REST API ideally, so that’s it’s more useful. I’d love to have it say ‘Acceptance Tests for #123’ or something similar.