oncheck -me

In preparation for a migration from 7.3 to 9.4, I've come across the following passage from page 3-49 of the Migration Guide... Partition header pages should not be full; key descriptors will occupy slightly more space after conversion to Dynamic Server 9.40. Use the oncheck -me command to compress extents and reduce the amount of storage used in partition headers. I'd like to know more about the oncheck -me command such as...does this command require exclusive use of key systems tables or can it be run while users are still online? I have some databases where tables such as sysconstraints and syscolumns have large numbers of extents. Would this command help consolidate these tables? I've looked for information on this command but I can't find it referenced anywhere in the Administrator's Guide or Administrator's Reference and oncheck -? doesn't even list -me as a valid switch. I've also done a Google search which did not return anything usefull. I've opened a tech support case asking for information on this as well (the tech had never heard of oncheck -me either...he is looking into it). So after all that, can anyone here help provide some information about oncheck -me?