Hello, I found a thread last year (12 Feb, 29 June 2009) about this same symptom I am experimenting. The thread didn't have a clear conclusion.
I.e. I get such errors in my nightly build logs, driven by a perl script which uses LDAP. It seems this is intermittent: most builds succeed, and I do not know what is special about those which fail with this error. Also, trying from the command line (as Graham instructed) works fine, as for previous posters. It looks like a resource exhaustion issue!? Was a solution ever found to this issue? Thanks, Marc