Can ToolTip display more than 15 Lines?

Hey there, I'm trying to have my tooltip as a popup status indicator for our project and can't get it to display more than 15 lines?  The width and heigth are dynamically created correctly, just blank after 15 lines.  Any reason why or something to get around this?

void COXToolTipCtrlCustom::DisplayToolTip(CPoint& pt, BOOL bExtended /*= FALSE*/)
{
    CSize szPopup;
 ASSERT(::IsWindow(m_hWnd));
 int nWidth;  //autowidth of popup
 int nHeight;
    if (!m_bActivated || !m_pCurrentToolTip)
        return;

    m_bExtended = bExtended;

    //CString str = GetTooltipText(m_pCurrentToolTip);
    CString str = _T("1\n2\n3\n4\n5\n6\n7\n8\n9\n10\n11\n12\n13\n14\n15\n16\n1 7asdfad\n18\n19\n20");
 if (str.IsEmpty())
        return;
 
    m_wndPopupControl.SetTheme(new CXTPPopupPaintManager());
 m_wndPopupControl.RedrawControl();
 
 //Calculate the width and height of the box dynamically
    CRect rect = GetBoundsRect(str, m_pCurrentToolTip->nWidth);
    rect = CalculateInfoBoxRect(pt, m_pCurrentToolTip, rect);
 
    nWidth = rect.right - rect.left;
 nHeight = rect.bottom - rect.top;
 m_wndPopupControl.AddItem(new CXTPPopupItem(
  CRect(0, 0, nWidth, nHeight), NULL, RGB(255,255,225), 0));
 szPopup = CSize(nWidth, nHeight);

 CXTPPopupItem* pItemText = (CXTPPopupItem*)m_wndPopupControl.AddItem(
  new CXTPPopupItem(CRect(3, 2, 200, 200), _T(str)));
 pItemText->SetHyperLink(FALSE);
 
 m_wndPopupControl.SetPopupAnimation((XTPPopupAnimation )0);
 m_wndPopupControl.SetShowDelay(0);
 m_wndPopupControl.SetAnimateDelay(100);
 m_wndPopupControl.SetTransparency((BYTE)theApp.m_nTool TipTransparency);
 m_wndPopupControl.SetPopupSize(szPopup);
 m_wndPopupControl.AllowMove(0);
 m_wndPopupControl.Show(this);
}