I guess that the limit is imposed by the Windows control that a lot of
edit variations in VCL and third party libs are wrappers/extensions for.
The limit occurs in some older Windows versions. Dig into the WinAPI (or
is it called Win32) help that comes with Delphi, it is specified there
somewhere.

If it is the case, whatever you specify in control properties won't matter.

Regards,

/Dany