An activation object is the object used to store local variables and parameters to a function. Since a wrapper function is written in C, it has no such variables. However, the calling script function does, and it is often convenient to be able to access them. SE_ACTIVATION accesses the calling script function's activation object. If there is no calling script function, SE_ACTIVATION accesses the global object, just as SE_GLOBAL does. You can get the activation object by using SE_ACTIVATION,SE_VALUE but you cannot write to it.