Virtual Inheritance and Parameterized Constructors

Possible duplicate:
Default constructor and virtual inheritance

class Base
{
private:
    int number;
protected:
    Base(int n) : number(n) {}
public:
    virtual void write() {cout << number;}     
};

class Derived1 : virtual public Base
{
private:
    int number;
protected:
    Derived1(int n, int n2) : Base(n), number(n2) {}
public:
    virtual void write() {Base::write(); cout << number;}
};

class Derived2 : virtual public Base
{
private:
    int number;
protected:
    Derived2(int n, int n2) : Base(n), number(n2) {}
public:
    virtual void write() {Base::write(); cout << number;}
};

class Problematic : public Derived1, public Derived2
{
private:
    int number;
public:
    Problematic(int n, int n2, int n3, int n4) : Derived1(n, n2), Derived2(n, n3), number(n4) {}
    virtual void write() {Derived1::write(); Derived2::write(); cout << number;}
};

int main()
{
    Base* obj = new Problematic(1, 2, 3, 4);
    obj->write();
}

In other words:

Base
| \
|  \
|   \
|    \
D1   D2
|    /
|   /
|  /
| /
Problematic

I am trying to get "1 2 1 3 4" in the output. The compiler, however, continues to complain that I need a constructor without parameters in Base, but when I add it, "1" turns into garbage. Any ideas on how to approach him? Is it even possible to enable a diamond pattern with a parameterized constructor?