why struct REQUEST 's member var container is void **

[李金为炜]

Hi,   I am studying freeradius0.5 ��s source.When I check the struct REQUEST ��s member var, I find that the container is double pointer.But I checked the other source code,it considered container is a point. i.e. request->container = rad_malloc(sizeof(REQNODE));(in rl_add function)   Hawinr Li