Windows ldp.exe kills openldap 2.4.23

Hello -

I just found that ldp.exe tool that comes with Windows is able to successfully kill OpenLDAP 2.4.23 when one tries tp modify DN and submits an empty old DN. Log files on openldap show this:

Dec 29 15:19:32 ottawa slapd[11818]: conn=1000 op=2 do_modrdn Dec 29 15:19:32 ottawa slapd[11818]: do_modrdn: dn () newrdn (C=US) newsuperior () Dec 29 15:19:32 ottawa slapd[11818]: >>> dnPrettyNormal: <> Dec 29 15:19:32 ottawa slapd[11818]: <<< dnPrettyNormal: <>, <> Dec 29 15:19:32 ottawa slapd[11818]: >>> dnPrettyNormal: <C=US> Dec 29 15:19:32 ottawa slapd[11818]: <<< dnPrettyNormal: <c=US>, <c=us> Dec 29 15:19:32 ottawa slapd[11818]: conn=1000 op=2 MODRDN dn=""

Is this a know bug (see ITS#6570) or something new? Is there a workaround it?