Attempting to login with ldap authentication enabled via the active directory plugin failed, with a valid, cached, user name and password.

On the Hudson Configuration page, inside the Active Directory Configuration, Advanced, section, pressing the "Test" button, resulted in "Success".

Reverting the plugin back to 1.16 put things back to working order.

Here is the stack trace from the log.

Nov 17, 2010 8:18:32 AM hudson.security.HudsonFilter doFilter
FINER: ENTRY

Nov 17, 2010 8:18:32 AM hudson.security.AuthenticationProcessingFilter2 onUnsuccessfulAuthentication
INFO: Login attempt failed
org.acegisecurity.BadCredentialsException: Either no such user 'kgraham' or incorrect password
at hudson.plugins.active_directory.ActiveDirectoryUnixAuthenticationProvider.retrieveUser(ActiveDirectoryUnixAuthenticationProvider.java:86)
at org.acegisecurity.providers.dao.AbstractUserDetailsAuthenticationProvider.authenticate(AbstractUserDetailsAuthenticationProvider.java:119)
at org.acegisecurity.providers.ProviderManager.doAuthentication(ProviderManager.java:195)
at org.acegisecurity.AbstractAuthenticationManager.authenticate(AbstractAuthenticationManager.java:45)
at org.acegisecurity.ui.webapp.AuthenticationProcessingFilter.attemptAuthentication(AuthenticationProcessingFilter.java:71)
at org.acegisecurity.ui.AbstractProcessingFilter.doFilter(AbstractProcessingFilter.java:252)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.ui.basicauth.BasicProcessingFilter.doFilter(BasicProcessingFilter.java:173)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at org.acegisecurity.context.HttpSessionContextIntegrationFilter.doFilter(HttpSessionContextIntegrationFilter.java:249)
at hudson.security.HttpSessionContextIntegrationFilter2.doFilter(HttpSessionContextIntegrationFilter2.java:66)
at hudson.security.ChainedServletFilter$1.doFilter(ChainedServletFilter.java:87)
at hudson.security.ChainedServletFilter.doFilter(ChainedServletFilter.java:76)
at hudson.security.HudsonFilter.doFilter(HudsonFilter.java:164)
at winstone.FilterConfiguration.execute(FilterConfiguration.java:195)
at winstone.RequestDispatcher.doFilter(RequestDispatcher.java:368)
at winstone.RequestDispatcher.forward(RequestDispatcher.java:333)
at winstone.RequestHandlerThread.processRequest(RequestHandlerThread.java:244)
at winstone.RequestHandlerThread.run(RequestHandlerThread.java:150)
at java.lang.Thread.run(Thread.java:619)

Nov 17, 2010 8:18:32 AM org.acegisecurity.ui.AbstractProcessingFilter unsuccessfulAuthentication
FINE: Authentication request failed: org.acegisecurity.BadCredentialsException: Either no such user 'kgraham' or incorrect password

Nov 17, 2010 8:18:32 AM org.acegisecurity.ui.AbstractProcessingFilter unsuccessfulAuthentication
FINE: Updated SecurityContextHolder to contain null Authentication

Nov 17, 2010 8:18:32 AM org.acegisecurity.ui.AbstractProcessingFilter doFilter
FINE: Request is to process authentication

Nov 17, 2010 8:18:32 AM hudson.security.ChainedServletFilter doFilter
FINER: ENTRY

Nov 17, 2010 8:18:32 AM hudson.security.HudsonFilter doFilter
FINER: ENTRY