what is NO_CONTENT_TYPE?

["Kirby Zhou" <kirbyzhou@xxxxxxxxxxx>]

I can not build glusterfs-2.0.0rc1 under RHEL-5.2.It shows that below

make[5]: Entering directory
`/opt/rpmbuild/BUILD/glusterfs-2.0.0rc1/mod_glusterfs/apache/2.2/src'
ln -sf ../../../../mod_glusterfs/apache/2.2/src/mod_glusterfs.c
../../../../mod_glusterfs/apache/2.2/src/mod_glusterfs-build.c
apxs -c -o mod_glusterfs.la -Wc,-g3 -Wc,-O0 -DLINUX=2 -D_REENTRANT
-D_GNU_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
-D__USE_FILE_OFFSET64 -I../../../../libglusterfsclient/src
-L../../../../libglusterfsclient/src/.libs/ -lglusterfsclient
mod_glusterfs-build.c 
/usr/lib64/apr-1/build/libtool --silent --mode=compile gcc -prefer-pic -O2
-g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector
--param=ssp-buffer-size=4 -m64 -mtune=generic  -DLINUX=2 -D_REENTRANT
-D_GNU_SOURCE -pthread -I/usr/include/httpd  -I/usr/include/apr-1
-I/usr/include/apr-1  -g3 -O0 -I../../../../libglusterfsclient/src -DLINUX=2
-D_REENTRANT -D_GNU_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
-D__USE_FILE_OFFSET64  -c -o mod_glusterfs-build.lo mod_glusterfs-build.c &&
touch mod_glusterfs-build.slo
...
mod_glusterfs-build.c:1351: error: 'NO_CONTENT_TYPE' undeclared (first use
in this function)
...