diff -ur lighttpd-1.4.32-orig/src/network_writev.c lighttpd-1.4.32/src/network_writev.c
--- lighttpd-1.4.32-orig/src/network_writev.c	2012-08-31 14:11:20.000000000 +0000
+++ lighttpd-1.4.32/src/network_writev.c	2013-02-05 16:00:48.000000000 +0000
@@ -30,6 +30,34 @@
 #define LOCAL_BUFFERING 1
 #endif
 
+size_t network_write_get_max_chunks(void) {
+	static size_t max_chunks = 0;
+	
+	/* Cache the results, since sysconf() is expensive on some platforms */
+	if (max_chunks)
+		return max_chunks;
+
+#if defined(_SC_IOV_MAX) /* IRIX, MacOS X, FreeBSD, Solaris, ... */
+	max_chunks = sysconf(_SC_IOV_MAX);
+#elif defined(IOV_MAX) /* Linux x86 (glibc-2.3.6-3) */
+	max_chunks = IOV_MAX;
+#elif defined(MAX_IOVEC) /* Linux ia64 (glibc-2.3.3-98.28) */
+	max_chunks = MAX_IOVEC;
+#elif defined(UIO_MAXIOV) /* Linux x86 (glibc-2.2.5-233) */
+	max_chunks = UIO_MAXIOV;
+#elif (defined(__FreeBSD__) && __FreeBSD_version < 500000) || defined(__DragonFly__) || defined(__APPLE__) 
+	/* - FreeBSD 4.x
+	 * - MacOS X 10.3.x
+	 *   (covered in -DKERNEL)
+	 *  */
+	max_chunks = 1024; /* UIO_MAXIOV value from sys/uio.h */
+#else
+#error "sysconf() doesnt return _SC_IOV_MAX, please file a bug at www.lighttpd.net"
+#endif
+	
+	return max_chunks;	
+}
+
 int network_write_chunkqueue_writev(server *srv, connection *con, int fd, chunkqueue *cq, off_t max_bytes) {
 	chunk *c;
 
@@ -42,27 +70,12 @@
 			off_t toSend;
 			ssize_t r;
 
-			size_t num_chunks, i;
+			size_t max_chunks, num_chunks, i;
 			struct iovec *chunks;
 			chunk *tc;
 			size_t num_bytes = 0;
-#if defined(_SC_IOV_MAX) /* IRIX, MacOS X, FreeBSD, Solaris, ... */
-			const size_t max_chunks = sysconf(_SC_IOV_MAX);
-#elif defined(IOV_MAX) /* Linux x86 (glibc-2.3.6-3) */
-			const size_t max_chunks = IOV_MAX;
-#elif defined(MAX_IOVEC) /* Linux ia64 (glibc-2.3.3-98.28) */
-			const size_t max_chunks = MAX_IOVEC;
-#elif defined(UIO_MAXIOV) /* Linux x86 (glibc-2.2.5-233) */
-			const size_t max_chunks = UIO_MAXIOV;
-#elif (defined(__FreeBSD__) && __FreeBSD_version < 500000) || defined(__DragonFly__) || defined(__APPLE__) 
-			/* - FreeBSD 4.x
-			 * - MacOS X 10.3.x
-			 *   (covered in -DKERNEL)
-			 *  */
-			const size_t max_chunks = 1024; /* UIO_MAXIOV value from sys/uio.h */
-#else
-#error "sysconf() doesnt return _SC_IOV_MAX ..., check the output of 'man writev' for the EINVAL error and send the output to jan@kneschke.de"
-#endif
+			
+			max_chunks = network_write_get_max_chunks();
 
 			/* build writev list
 			 *