You do not have `#define NULL 0' in your system wide .h files or you do not have the correct setup for your include dirs. You can put it in qmail.h, I donno if it will solve your prblem, but worth to try it. Take note that other programs may also fail to compile on that machine.
Hans Westerbeek wrote: > ./compile maildir++.c > maildir++.c: In function `quota_check': > maildir++.c:214: `NULL' undeclared (first use in this function)