onpload/HPL migration from 7.23 to 7.3 problem

Here's the scenario. Yesterday we migrated from 7.23 to 7.3 IDS. Part of the preparation was dbexport of the onpload database. Did the dbimport, no errors reported. Here's the problem. HPL won't work. All the devices in the onpload are missing AND cannot be modified(?!). Current theory we are investigating is that Informix modified the column lay out of the onpload between versions. Has anyone seen this problem? Any suggestions? Paul Storm