Grid Col/row lines improvements

(using Delphi 4 Pro) - descendants of TCustomGrid such as DrawGrid and
StringGrid components seem to have  a problem when grid linewidth is > 1 and
fixed and variable options are used. (e.g. gofixedvertline True, govertlines
= False, in that the variable areas of the grid is still drawn etc.
I have been looking at fixing this, and providing different colors etc for
lines in the fixed/non-fixed areas.
The simple way would be to modify the Grids.pas unit - only needs about 12
lines of code changing, but then I can't seem to rebuild the grids package
so that changes are seen in the object inspector etc.
So am obliged to subclass and repeat lots of code etc.

Q. Is this fixed in Delphi 5?
Q. Have other people already noticed and fixed this?
If not, I am happy to share my code changes here if that is helpful.
Best Regards
Chris H.