IDS 9.30 on a virtualised HP-UX platform; "Checkpoint Stalled"

Hi there I'm concious this is an old unsupported IDS version (IDS 9.30HC5) but as part of a migration I have to do a proof of concept. We've got the dbserver installed on a virtualised platform (basically it's a direct lift from $PARENT_COMPANY's installation copied onto the target machine and the installserver/RUN_AS_ROOT.server stages run). It initialises OK and I can create the databases and extra chunks we need etc etc but when I come to dbimport our exported databases, it gets so far and the we get the dreaded "Blocked:CKPT" message on onstat -u. Trying onmode -c results in the "Checkpoint has stalled and is not complete" message. We're loading the dbimport with no logging mode set, and have 50 AIO VPs, which should be sufficient. onstat -u for the dbimport thread is showing "---PX--". Any clues please? Yes I know this is not a standard procedure...