I posted this on bug tracker on source forge but since it was the only bug in there and it appears the bug tracking system may not yet be fully configured I am posting here just in case.
Looking at the source of release 0.16 it appears several functions will leak memory everytime they are called. All functions that use AMX_GET_STRING should be checked.
The issue is AMX_GET_STRING returns a dynamically allocated char pointer. If this pointer is not stored in a data structure it should be freed. Several function in engine/meta_api.cpp never free the pointer returned by AMX_GET_STRING. The following function will leak memory every time called:
Other routines use AMX_GET_STRING but at first glance I could not determine if they leaked memory since they are passing data structures to the engine.