Possible, but its just 1 more line of boiler plate code a plugin needs.
Code:
//------------------------
// USER_PLUGIN.cpp side
//------------------------
#include "avisynth.h"
...
// New 2.6 requirment!!!
// Declare the server pointer
ServerFunctions *serverFunctionsVectors = 0;
extern "C" __declspec(dllexport) const char* __stdcall
AvisynthPluginInit2(IScriptEnvironment* env) {
// Add the name of our function
env->AddFunction("Plugin", "c", Create_Plugin, 0);
return "Plugin text";
}