How ActionScript can communicate to C/C++ dll or Lib?

Hi,

We are developing a Flash application based on Windows CE 6.0 R3 and the application is intended to work with Adobe flash plug in available in WinCE R3 Internet Explorer. Application need to communicate with middleware libraries written in C/C++. Flash screens uses Action Script 3.0. We would like to know how a Flash application (Action script program) can communicate with a native (C/C++) dll/lib?

Rgds,

Gloria