global malloc/free replacements

Hi, we need to find a way to replace malloc/free calls globally (everywhere, also in libzend/TSRM). These must be replaced, because the allocator functions on most systems are not reentrant. They use a static data structure to determine the free blocks. Therefore, all mallocs/frees must go through exactly one set of functions which must be mutexed. It would be enough, if we could define the replacement functions in one place (one header file), but I am not sure where that place would be. The SAPI modules must determine which replacement functions to use (threaded web-servers provide these usually), but I don't think libzend/TSRM include anything from the PHP side. What we could do is to pass a prefix to libzend/TSRM at configure time which would be the prefix of the replacement functions. Any ideas? -- Regards, Sascha Schumann Consultant