Error compiling timestamp.c in 7.4

I get the following compiler error messages when doing a make on current CVS:
gcc -O2 -Wall -Wmissing-prototypes -Wmissing-declarations -fpic -I../../../../src/interfaces/ecpg/include
-I../../../../src/include/utils-I../../../../src/include   -g  -c timestamp.c -o timestamp.o
 
timestamp.c: In function `tm2timestamp':
timestamp.c:71: parse error before `86400000000LL'
timestamp.c:73: parse error before `long'
timestamp.c:76: parse error before `>='
timestamp.c:76: parse error before `<'
make[4]: *** [timestamp.o] Error 1

I use the following to run config:
./configure --prefix=/usr/local/pgsql --enable-integer-datetimes --with-pgport=5433

I am doing this on a RH 6.1 system.