Serialization template classes

Hello group,

I've written a serialization class which serializes arbitrary objects to
by "Block" representation. A template exists for POD objects, as do some
specializations, like:

template<> class Serializer<std::string> {
  public:
    static void Serialize(const std::string &Input, Block &Output) {
      Serializer<unsigned int>::Serialize(Input.size(), Output);
      Output.Increment(Input.size());
      std::copy(Input.begin(), Input.end(), Output.endptr() - Input.size());
    }
[...]

Those all work fine. Now I wanted to introduce a template that could
reduce a map which contains arbitrary types:

template<typename T1, typename T2> class Serializer< std::map<T1, T2> > {
  public:
    static void Serialize(const std::map<T1, T2> &Input, Block &Output) {
      Serializer<unsigned int>::Serialize(Input.size(), Output);
      std::map<T1, T2>::const_iterator i;
      for (i = Input.begin(); i != Input.end(); i++) {
        Serializer<T1>::Serialize(i->first, Output);
        Serializer<T2>::Serialize(i->second, Output);
      }
    }

The compiler however now complains with a *very* weird error:

Common/Serializer.hpp: In static member function static void
Serializer<std::map<T1, T2, std::less<_Key>,
std::allocator<std::pair<const _Key, _Tp> > > >::Serialize(const
std::map<T1, T2, std::less<_Key>, std::allocator<std::pair<const _Key,
_Tp> > >&, Block&):
Common/Serializer.hpp:61: error: expected `;' before i
Common/Serializer.hpp:62: error: i was not declared in this scope

What am I doing wrong?

Kind regards,
Johannes

--
"Meine Gegenklage gegen dich lautet dann auf bewusste Verlogenheit,
verl?sterung von Gott, Bibel und mir und bewusster Blasphemie."
         -- Prophet und Vision?r Hans Joss aka HJP in de.sci.physik
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