how does template<template<...> op> function(op<...>) work?

[Piotr Sawuk]

Iis there some problem with type-matching of template template-parameters?
Is there any error/misunderstanding on my side?
In g++ 4.1.2 I get "no matching function for call to ... operator="
when I compile "o=o*i;" with

#include <algorithm>

template<typename iter_, typename val_>
struct stl_algorithm_class
{//class encapsulating all stl-algorithms operating on iterator-ranges...
        template<class op_,typename iter2_=iter_>
        class stl_binary_operation
        {
                stl_algorithm_class<iter_> v1;
                stl_algorithm_class<iter2_> v2;
                public:
                stl_binary_operation(stl_algorithm_class<iter_> v,
                                     stl_algorithm_class<iter2_> w) : v1(v), 
v2(w) {}
                template<typename iter3_>
                iter3_ operator()(stl_algorithm_class<iter3_> o)
                {return std::transform(v1.start,v1.tail,v2.start,o.start, 
op_());}
        };
        template<class op_,typename iter2_>
        class stl_unary_operation
        {//similar
        };

        iter_ start,tail;
        stl_algorithm_class(const iter_& s, const iter_& e) : start(s), tail(e) 
{}

        template<typename iter2_,typename val2_>
        iter_ operator=(const stl_algorithm_class<iter2_,val2_>& t)
        {return std::copy(t.start,t.tail,start);}
        template<template<class,typename> class stl_operator_,class iter2_,
                 typename val1_,class op_, typename val2_>
        iter_ operator=(typename stl_algorithm_class<iter2_,val1_>::template
                                               stl_operator_<op_,val2_>& o)
        {return o(*this);}
        
        
        template<typename iter2_>
        friend stl_binary_operation<std::multiplies<val_>,iter2_ > 
                operator*(const stl_algorithm_class<iter_>& a,
                          const stl_algorithm_class<iter2_>& b)
        {return stl_binary_operation<std::multiplies<val_> ,iter2_>(a,b);}
};

int n(16),s1[16],s2[16];
stl_algorithm_class<int*,int> i(s1,s1+n),o(s2,s2+n);

-- 
Better send the eMails to netscape.net, as to
evade useless burthening of my provider's /dev/null...

P