The distribution of Ant 1.8.2 is broken on Mac.
January 16, 2012
You have to patch Ant in order to run ssh from it. It needs a ssh implementation that isn’t bundled with the default distribution. If you just define a task like this:
<sshexec host="somehost" username="dude" password="yo" command="touch somefile"/>
Then you will get the error message below back.