Text turns to mush

[zapper222]

I am using this code to print color text to a rich edit box:

void CRichEditDlg::OnBnClickedButton1()
{
	// TODO: Add your control notification handler code here
	CHARFORMAT Cfm;

	m_Richer.GetSelectionCharFormat(Cfm);

	Cfm.cbSize = sizeof(CHARFORMAT);
	Cfm.dwMask = CFM_COLOR|CFM_BOLD;
	Cfm.dwEffects = CFE_BOLD; 
	Cfm.crTextColor = RGB(0,0,255);

	m_Richer.SetSelectionCharFormat(Cfm); 

	CString text = "Now is the time for all good men to come to the aid of the party";

   SETTEXTEX SetTextEx;
   SetTextEx.codepage = CP_ACP;
   SetTextEx.flags = ST_SELECTION;

   m_Richer.SetSel(-1,-1);
   m_Richer.SendMessage(EM_SETTEXTEX,(WPARAM)&SetTextEx, (LPARAM) (LPCTSTR)text);
}

Everything works well, the text prints to the box and the colors are correct, but when I scroll up or down using the thumb, all the text gets distorted. Any ideas?

Thanks
Zapper222