error C2248: '()' : cannot access private member declared in class ...

I don't know what's wrong with me today, but it's taking way too long to get this little piece of code to compile properly:

Code:

#ifndef STRUTILS_H_INCLUDED_FEB_14_2008
#define STRUTILS_H_INCLUDED_FEB_14_2008

#include <string>
#include <algorithm>
#include <functional>
#include <cctype>

#ifdef UNICODE
#	define TCHAR	wchar_t
#else
#	define TCHAR	char
#endif


namespace StrUtils
{
	template <typename T>
	class CharLessNoCase	:	public std::binary_function<T, T, bool>
	{
		bool operator()( T  c1, T  c2 )
		{
			return (tolower( static_cast<unsigned T>(c1) ) <
				tolower( static_cast<unsigned T>(c1) ));
		}
	};


	template <typename T>
	bool StringCompareNoCase(  std::basic_string<T>&  str1,
				   std::basic_string<T>&  str2 )
	{
		return std::lexicographical_compare( str1.begin(), str1.end(),
						     str2.begin(), str2.end(),
						     CharLessNoCase<T>() );
	}
}

#endif	// STRUTILS_H_INCLUDED_FEB_14_2008

VC++ 6.0 is saying:

c:\program files\microsoft visual studio 6.0\vc98\include\xutility(60) : error C2248: '()' : cannot access private member declared in class 'StrUtils::CharLessNoCase<unsigned short>'
d:\vss_root\devel\include\base\strutils.h(24) : see declaration of '()'
d:\vss_root\devel\include\base\strutils.h(38) : see reference to function template instantiation 'bool __cdecl std::lexicographical_compare(unsigned short *,unsigned short *,unsigned short *,unsigned short *,class StrUtils::CharLessNoCase<unsigned short>)' being compiled

Even Comeau is choking on it, so it has to be something I'm doing wrong, but I just can't see what it is...

Perhaps it's because your operator() is private?

Yeah, I just noticed that. Doh!