EndDrag bug in Delphi 3?

I have ported Delphi 1 code to Delphi 3 which fails on the EndDrag method
for TTreeView, TOutline, TPanel, and TShape objects in Delphi 3.

Is this a confirmed bug in Delphi 3 and is there an update version which
addresses this bug?  I have Delphi 3 (Build 5.83) which I thought was the
latest release.