When I click the Poll SCM link for a job it brings up a window complaining about not using a HTTP POST. The message is below.

You must use POST method to trigger builds. (From scripts you may instead pass a per-project authentication token, or authenticate with your API token.) If you see this page, it may be because a plugin offered a GET link; file a bug report for that plugin.

Workaround: Click the proceed button on the new web page and it will poll properly. You then have to return to the Job via the breadcrumbs.