I updated Jenkins from 1.413? to 1.417 and associated static analysis (checkstyle) plugins.
I changed one of my jobs to report checkstyle.
When I ran it it told me it couldn't find ant.

When I checked the job history, the ant version was removed.

<hudson.tasks.Ant>
<targets>continuous_integration</targets>

• <antName>ant_1.7.1</antName>
  <antOpts>-Xms1024m -Xmx1024m</antOpts>
  <buildFile>build.Jenkins.xml</buildFile>

Looking at the job config page, there is no longer an option to specify which ant version is desired.
The config Jenkins page still showed the and install being available, but there was no way to re?-pick it for the job.