Deadlock while using boost::asio::deadline_timer in Windows dll

I am trying to use Boost-Deadlinetimer inside a DLL, which is loaded using boost::dll::shared_library. Following code-snippets are reduced to the essentials.

Example.h:

#include <boost/asio.hpp>
class Example  
{  
public:  
    Class() : m_timer(m_ioService) { } 
    virtual ~Class() { }  
    //...    
private:  
    boost::asio::io_service m_ioService;  
    boost::asio::deadline_timer m_timer;
    //...
};

Example.cpp:

#include "Example.h"
#include <boost/config.hpp>
//...
extern "C" BOOST_SYMBOL_EXPORT Example MyExample;
Example MyExample;

Main.cpp:

#include <boost/dll/Import.hpp>
//...
boost::dll::shared_library lib("Example.dll", boost::dll::load_mode::Default_mode);
//...

My Problem is that there is a deadlock while loading the compiled dll as long as m_timer is in the constructor's initialization list.

When replacing m_timer by a boost::shared_ptr and initializing that in the constructor (or a subsequent function), then there is no deadlock while loading the dll but a deadlock while unloading the dll.

Anyway, I cannot really use a global deadline timer object in a Windows dll.