Trying to create an account for automatic JDK download (see /descriptorByName/hudson.tools.JDKInstaller/enterCredential) seems to have a problem, if I got it right. If going to create an oracle account at http://jenkins-ci.org/oracleAccountSignup and reading the linked Terms of Use you might stumble across paragraph 7 (btw: The Terms of Use at Oracle cannot deal with an attached jsessionid...):

7. Security, Passwords and Means of Accessing the Site and Content

You agree not to access or use the Site in any manner that could damage, disable, overburden, or impair any Oracle accounts, computer systems or networks. You agree not to attempt to gain unauthorized access to any parts of the Site or any Oracle accounts, computer systems or networks. You agree not to interfere or attempt to interfere with the proper working of the Site or any Oracle accounts, computer systems or networks. You agree not to use any robot, spider, scraper or other automated means to access the Site or any Oracle accounts, computer systems or networks without Oracle's express written permission.

Tell me, if I am wrong, but JDK installation through Jenkins looks like an automated task to me and thus infringes the Terms of Use.