I was having similar problems (with apacheds 0.9 on Linux client-server) as mentioned in Ref: http://issues.apache.org/jira/browse/DIRSERVER-586, so I did some more tests using the attached test case. Here is my observation

Client Env
1. Test running On Windows
- The test hangs (intermittently) with jdk1.5.0_04, but it works fine with jdk1.5.0_07, j2sdk1.4.2_04

2. Tets running on Linux (Linux 2.4.20-8smp)
- The test hangs (always) with jdk1.5.0_07 but works fine j2sdk1.4.2_06

Server Env
apacheds 1.0RC3 on Linux 2.4.20-8smp using jdk1.5.0_07

I had to modify the source code of the test case attached in JIRA to run it on jdk1.4, modified code is attached.

I've doubts on whether it is apacheds issue or sun jndi issue. Apacheds dev team could investigate it further.

As I mentioned, I'm facing this issue on apacheds 0.9 so I was hoping that upgrade to 1.0RC3 would probably solve this problem. I did not had any repeatable test case with apacheds 0.9. But the test case in JIRA is definitely repeatable on apacheds 1.0 RC3.