I am working on an MS Office Addin developed in ATL COM. There is an option dialog which has a tab control inside having Property Sheets like this

Code:
class COptions_Buffers : public WTL::CPropertyPage<IDD_OPTIONS_BUFFERS>
{
..........................................
..........................................
}
These property sheets are invoked using DoModal

Code:
COptionsBox::COptionsBox(const HINSTANCE & hResourceInstance,
						 DWORD * pUpdateCommand,
						 const DWORD dwMask):
	m_hResourceInstance(hResourceInstance)
{
	//WTL::CPropertySheet sheet( CUtils::GetResourceString( IDS_GUI_OPTIONS_OPTIONS ).c_str() );
	COptionsSheet sheet( CUtils::GetResourceString_( IDS_GUI_OPTIONS_OPTIONS ).c_str() );

	sheet.m_psh.dwFlags &= ~PSH_HASHELP;

	HICON hIcon = LoadIcon(m_hResourceInstance, MAKEINTRESOURCE(IDI_ICON1));
	sheet.m_psh.hIcon = hIcon;
	sheet.m_psh.dwFlags |= PSH_USEHICON;

	//COptions_CriticalChain	page8;
	COptions_Buffers		page1;
	//COptions_Statusing		page10;
	COptions_Update			page9;
	COptions_UnDo			page6;
	COptions_Trend			page5;
	COptions_CCPMView		page2;
	COptions_Colors			page3;
	COptions_Toolbar		page4(pUpdateCommand);
	//COptions_Fields			page11;

	if(dwMask & 1) //general
	{
		throw EXCEPTION_IMPLEMENTATION;
		//sheet.AddPage(page8);
	}

	if(dwMask & 2) //buffers
	{
		sheet.AddPage(page1);
	}

	/*if(dwMask & 4)
	{
		sheet.AddPage(page10);
	}*/

	if(dwMask & 8)
	{
		sheet.AddPage(page9);
	}

	if(dwMask & 16)
	{
		sheet.AddPage(page6);
	}

	if(dwMask & 32)
	{
		sheet.AddPage(page5);	
	}

	if(dwMask & 64) //view
	{
		sheet.AddPage(page2);
	}

	if(dwMask & 128)
	{
		sheet.AddPage(page3);
	}

	if(dwMask & 256)
	{
		sheet.AddPage(page4);
	}

	if(dwMask & 512)
	{
		throw EXCEPTION_IMPLEMENTATION;
		//sheet.AddPage(page11);
	}

	sheet.DoModal();
}
The main parent window has got an Apply button which is by default disabled and I want to enable it when the user clicks on any of the radio button inside its child property page. How can I do that??

Thanks in Advance