🚀 go-pugleaf

I keep getting the following error

[Linker Error] Unresolved external 'GradientFill' referenced from 
C:\PROGRAM FILES\BORLAND\CBUILDER5\PROJECTS\...\FRMMAIN.OBJ

But code insight shows the prototype/parameters

it is declared in Windows.hpp
function GradientFill; external msimg32 name 'GradientFill';

  & wingdi.h
WINGDIAPI BOOL  WINAPI GradientFill( IN HDC, IN PTRIVERTEX, IN ULONG, IN 
PVOID, IN ULONG, IN ULONG);


Anybody get this to work? Can think of what I might be doing wrong? Know 
the phase of the moon? :)

Any help would be greatly appreciated. Code follows:

DC
BCB5ent

//---------------------------------------------------------------------------
void __fastcall TMainForm::FormPaint(TObject *Sender)
{
    int startColor = ColorToRGB(clBlue);
    int endColor   = ColorToRGB(clBlack);
    TRIVERTEX      vert[2];
    GRADIENT_RECT  gRect;

    vert[0].x      = 0;
    vert[0].y      = 0;
    vert[0].Red    = GetRValue(startColor);
    vert[0].Green  = GetGValue(startColor);
    vert[0].Blue   = GetBValue(startColor);
    vert[0].Alpha  = 0x0000;

    vert[1].x      = 0;
    vert[1].y      = 0;
    vert[1].Red    = GetRValue(endColor);
    vert[1].Green  = GetGValue(endColor);
    vert[1].Blue   = GetBValue(endColor);
    vert[1].Alpha  = 0x0000;

    gRect.UpperLeft  = 0;
    gRect.LowerRight = 1;
    GradientFill(pnlEventEditor->Handle,
                 vert, 2,
                 &gRect, 1,
                 GRADIENT_FILL_RECT_H
                );
} //End FormPaint()
//---------------------------------------------------------------------------