If you don't mind having Java running, this one's quite nice: http://www.iit.edu/~gawojar/ldap/
If you're doing this from Windows, there's a mini-util called ldp.exe, which is really snappy (compared to iPlanet's Java doom).
It is in the support tools section on your Windows CD. eg. on my Win2k3 cd there is a folder called "support" in which you find a folder named "tools" that contains an installer "suptools.msi" that will install the tools. The actual ldp.exe is inside the support.cab in that same folder.
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