Ok, I lied about it working... TCP_NODELAY?

Configure worked, compile failed :)

gcc -pipe -O2 -Wall -Wmissing-prototypes -Wmissing-declarations
-I../../../src/include   -c -o pqcomm.o pqcomm.c
pqcomm.c: In function `StreamConnection':
pqcomm.c:395: `TCP_NODELAY' undeclared (first use in this function)
pqcomm.c:395: (Each undeclared identifier is reported only once
pqcomm.c:395: for each function it appears in.)