default value initializer in templatized class

I want to create a templatizable class which includes a default value for the templatized data type.  The following oversimplified example will work for atomic types like int and BOOL but not for data types that are structures or classes:

template <class DataType, DataType DefaultValue>
class CMyClass
{
protected:
  DataType m_Data;
public
  CMyClass() {m_Data = DefaultValue;}
}; //end CMyClass

I get several errors if I try to instantiate the following:
CMyClass<CString, "default string value"> MyObject;

I found that CString is not a valid type for a template argument because structures are not allowed.  MSDN (my C++ documentation) says to use a pointer instead if that is the case, but when I have tried that, I get an error like "expected constant value" because I have to instantiate it something like this:

const CString DefaultValue("default string value")
CMyClass<CString*, &DefaultValue> MyObject;

and &DefaultValue is where it expects a constant value and I can't give it one.  I use CString as an example, but I want to be able to use this on custom classes as well (all of which would support operator= so that the templatized constructor code m_Data = DefaultValue would work) otherwise, there are a variety of alternative solutions I could use just for strings.

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I want to be able to make a similar class for arrays like this:

template <class DataType, int nNumElements, const DataType* pDefaultValue>
class CMyArrayClass
{
protected:
  DataType m_arData[nNumElements];
public:
  CMyClass()
  {
    for (int i=0; i<nNumElements; i++)
       m_arData[i] = pDefaultValue[i];
  }
}; //end CMyArrayClass

I have tried the above code using a char array as follows:
CMyArrayClass<char, 4, "test"> MyObject;
but I get an error that "test" is an invalid template argument (even though it is a const char*).  If I use NULL instead, it works, but that doesn't help me because I want to pass in an initial value other than a non-value like NULL.

So what can I do?