I got this error trying to log on to the hosted demo. When I back-button and click on Proceed without Registration again, I get the "type the pictured text" page again. I type the text, and I get the proceed without registration page again. A cycle.

But as I write, I notice the "type the pictured text" page reloading. I do, and it works.

Yes, this is perhaps a completely worthless bug description (though, to my credit, this is the second time I've managed to get this to happen, and I did search for this already being posted). Sorry I don't have more meaningful information. You guys rock, and have my blessing to delete this report.

Code:
type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

java.lang.NullPointerException
	com.zimbra.zimbraDemo.demoAccountProvisioning.PopulateProvisionedAccount.loginAndGetAuthToken(PopulateProvisionedAccount.java:186)
	com.zimbra.zimbraDemo.demoAccountProvisioning.PopulateProvisionedAccount.makeSOAPCalls(PopulateProvisionedAccount.java:76)
	com.zimbra.zimbraDemo.demoAccountProvisioning.ProvisionAccountAndUpdate.PopulateDataInDemoAccount(ProvisionAccountAndUpdate.java:166)
	com.zimbra.zimbraDemo.demoAccountProvisioning.Provider.provide(Provider.java:154)
	com.zimbra.zimbraDemo.demoAccountProvisioning.DemoMailboxProvisioningServlet.doPost(DemoMailboxProvisioningServlet.java:94)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	com.zimbra.zimbraDemo.captcha.CheckCaptchaResponseServlet.doPost(CheckCaptchaResponseServlet.java:57)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note The full stack trace of the root cause is available in the Apache Tomcat/5.5.7 logs.
Apache Tomcat/5.5.7