C++ Sftp_ListNames Stops (wodSFTP / wodSFTP.NET / wodSFTPdll)

I am using the licensed version of the wodSFTPdll in Visual C++ .NET 2003 (unmanaged). At some point (in various parts of the program) a call to Sftp_ListNames causes the thread to stop. Pausing in debug mode shows this as the strack trace:

ntdll.dll!7c90eb94()
user32.dll!77d49418()
SftpDLL.dll!00817b6d()
SftpDLL.dll!0081aaf2()
SftpDLL.dll!00815ebf()
SftpDLL.dll!0081846b()
msvcp71d.dll!std::basic_string<char,std::char_traits<char>,std::allocator<char> >::c_str() Line 1095 C++
SftpDLL.dll!008182f1()
msvcp71d.dll!std::basic_string<char,std::char_traits<char>,std::allocator<char> >::c_str() Line 1095 C++
msvcp71d.dll!std::basic_string<char,std::char_traits<char>,std::allocator<char> >::c_str() Line 1095 C++
libeay32.dll!00730069()

the call back ListItems is never called so it is stopping before that. I've found disconnecting and then reconnecting solves this but there are many points where this can happen and it very slow to do this (and quite annoying).

Has anyone ever had any issues like this? Any suggestions or a solution (besides disconnecting/connecting)?