Eclipse 2.2 and higher reads registry key HKEY_LOCAL_MACHINE\Software\Borland\Database Engine\DLLPath and then checks the version of idapi32.dll found in that path. If not 18.104.22.168 then it forces the automatic download and upgrade of the BDE.
Some users are report that even after numerous upgrades of the BDE it keeps telling them that the wrong version is installed. This seems to happen when other software that uses the BDE is installed and writes a second path to the above key. One path gets the upgrade whilst the other is being checked for the correct version.
So for instance the registry key
c:\program files\borland\Borland Shared\BDE;c:\program files\borland\BDE
To correct, Open Windows control panel, run BDE Administrator. Look at the caption bar at the top of the program and make a note of the path displayed there (in our example c:\program files\borland\Borland Shared\BDE) - this is the CORRECT path. Then go to Start / Run / Regedit and find the key HKEY_LOCAL_MACHINE\Software\Borland\Database Engine. Right click on the DLLPath and select Edit, then remove the incorrect path including the semi colon so that it just contains the CORRECT path, in our example:
c:\program files\borland\Borland Shared\BDE