On Macs, the Computer Name will display as whatever DNS resolves to. The Inventory agent (/Library/Application\ Support/LANDesk/bin/ldiscan) reports Computer Name from the Mac's HostName parameter, not the ComputerName parameter (what you type into the Sharing Preferences Pane). In order to make these two the same, you can run the following command as root:
/usr/sbin/scutil --get ComputerName | /usr/sbin/scutil --set HostName $1
You can follow it with this command to update the inventory server:
/Library/Application\ Support/LANDesk/bin/ldiscan -t
[Edit: Command line parameters for ldiscan have changed since 9.6. While "--mini" no longer works, "-t" works on 9.6 and 9.5 (not sure of earlier versions)]