Problem drawing transparent bitmap using DrawTransparentBitmap exisitng ONLY in Win98 16bit color

Hello,

I'm using following function :
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void DrawTransparentBitmap(HDC hdc, HBITMAP hBitmap, int xStart,
                           int yStart, COLORREF cTransparentColor)
{
      BITMAP     bm;
      COLORREF   cColor;
      HBITMAP    bmAndBack, bmAndObject, bmAndMem, bmSave;
      HBITMAP    bmBackOld, bmObjectOld, bmMemOld, bmSaveOld;
      HDC        hdcMem, hdcBack, hdcObject, hdcTemp, hdcSave;
      POINT      ptSize;

      hdcTemp = CreateCompatibleDC(hdc);
      SelectObject(hdcTemp, hBitmap);   // Select the bitmap

      GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&bm);
      ptSize.x = bm.bmWidth;            // Get width of bitmap
      ptSize.y = bm.bmHeight;           // Get height of bitmap
      DPtoLP(hdcTemp, &ptSize, 1);      // Convert from device
      
      // to logical points
      
      // Create some DCs to hold temporary data.
      hdcBack   = CreateCompatibleDC(hdc);
      hdcObject = CreateCompatibleDC(hdc);
      hdcMem    = CreateCompatibleDC(hdc);
      hdcSave   = CreateCompatibleDC(hdc);
      
      // Create a bitmap for each DC. DCs are required for a number of
      // GDI functions.
      
      // Monochrome DC
      bmAndBack   = CreateBitmap(ptSize.x, ptSize.y, 1, 1, NULL);
      
      // Monochrome DC
      bmAndObject = CreateBitmap(ptSize.x, ptSize.y, 1, 1, NULL);
      
      bmAndMem    = CreateCompatibleBitmap(hdc, ptSize.x, ptSize.y);
      bmSave      = CreateCompatibleBitmap(hdc, ptSize.x, ptSize.y);
      
      // Each DC must select a bitmap object to store pixel data.
      bmBackOld   = (HBITMAP)SelectObject(hdcBack, bmAndBack);
      bmObjectOld = (HBITMAP)SelectObject(hdcObject, bmAndObject);
      bmMemOld    = (HBITMAP)SelectObject(hdcMem, bmAndMem);
      bmSaveOld   = (HBITMAP)SelectObject(hdcSave, bmSave);
      
      // Set proper mapping mode.
      SetMapMode(hdcTemp, GetMapMode(hdc));
      
      // Save the bitmap sent here, because it will be overwritten.
      BitBlt(hdcSave, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCCOPY);
      
      // Set the background color of the source DC to the color.
      // contained in the parts of the bitmap that should be transparent
      cColor = SetBkColor(hdcTemp, cTransparentColor);
      
      // Create the object mask for the bitmap by performing a BitBlt
      // from the source bitmap to a monochrome bitmap.
      BitBlt(hdcObject, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0,
            SRCCOPY);
      
      // Set the background color of the source DC back to the original
      // color.
      SetBkColor(hdcTemp, cColor);
      
      // Create the inverse of the object mask.
      BitBlt(hdcBack, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0,
            NOTSRCCOPY);
      
      // Copy the background of the main DC to the destination.
      BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdc, xStart, yStart,
            SRCCOPY);
      
      // Mask out the places where the bitmap will be placed.
      BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcObject, 0, 0, SRCAND);
      
      // Mask out the transparent colored pixels on the bitmap.
      BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcBack, 0, 0, SRCAND);
      
      // XOR the bitmap with the background on the destination DC.
      BitBlt(hdcMem, 0, 0, ptSize.x, ptSize.y, hdcTemp, 0, 0, SRCPAINT);
      
      // Copy the destination to the screen.
      BitBlt(hdc, xStart, yStart, ptSize.x, ptSize.y, hdcMem, 0, 0,
            SRCCOPY);
      
      // Place the original bitmap back into the bitmap sent here.
      BitBlt(hdcTemp, 0, 0, ptSize.x, ptSize.y, hdcSave, 0, 0, SRCCOPY);
      
      // Delete the memory bitmaps.
      DeleteObject(SelectObject(hdcBack,   bmBackOld));
      DeleteObject(SelectObject(hdcObject, bmObjectOld));
      DeleteObject(SelectObject(hdcMem,    bmMemOld));
      DeleteObject(SelectObject(hdcSave,   bmSaveOld));
      
      // Delete the memory DCs.
      DeleteDC(hdcMem);
      DeleteDC(hdcBack);
      DeleteDC(hdcObject);
      DeleteDC(hdcSave);
      DeleteDC(hdcTemp);
}
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I use function a lot and it works perfect. Recently , by chance i finded out
there's a problem in win98 ( second edition ) when using 16 BIT COLOR.

Here's example of how i use this function :

DrawTransparentBitmap(
            m_hMemDC ,
            HBITMAP(pictBubble),
            nBubblePosX,
            nBubblePosY,
            CLR_TRANSPARENT);

Here's my define of transparent color ( "clean" CYAN )
#define CLR_TRANSPARENT         RGB(0,255,255)

As i said , it works everywhere except win98 ( second edition ) when using 16 BIT COLOR.
As far as i know , each loaded image produces it's own palette. In some cases , it can
cause color to be changed to nearest color and obviously , transparency won't work in this
case since above function needs transparent color to be exact down to pixel.
So , i tried to use following to work it out :

cTransparentColor = GetNearestColor( hdc , CLR_TRANSPARENT );       

But , it didn't work.


Need your help ( it's pretty urgent ) , thanks !
P.S. I just prefer solution that won't force me to change everything , but a small patch ;)