Article on using 4.622 DB utilities against databases from earlier releases.
The link below may be helpful if you would like to be able to take advantage of recent new features of REORGDB or DBCHECK but are still using 4.621 or an older DP4 release.
a4000032.htm
Enhanced DBCHECK
The 4.623/4.527 Beta download now incorporates an important enhancement to DBCHECK: when you specify the command tail
-full dbcheck performs additional checks on the consistency of the index. These checks are more or less equivalent to the checks performed by dynachek. Although this makes dbcheck take somewhat longer to run, you are recommended to use this command tail when checking the intergrity of a live database. dynaback and dbbackup -copy have been updated to use this new option. For further details see
http://www.itimdp4.com/manpages/DP4Dev/Checking_the_Database_Integrity.htm#full