diff --git a/configure b/configure
index 460fcfcf..3ba1ec34 100755
--- a/configure
+++ b/configure
@@ -43,6 +43,7 @@ fi
 CC=${CC:-gcc}
 CXX=${CXX:-g++}
 CFLAGS=${CFLAGS:--O2}
+CPPFLAGS=${CPPFLAGS:-}
 CXXFLAGS=${CXXFLAGS:-\$(CFLAGS)}
 LDFLAGS=${LDFLAGS:-}
 XAPIAN_CONFIG=${XAPIAN_CONFIG:-xapian-config}
@@ -91,6 +92,7 @@ First, some common variables can specified via environment variables:
 
 	CC		The C compiler to use
 	CFLAGS		Flags to pass to the C compiler
+        CPPFLAGS	Flags to pass to the C preprocessor
 	CXX		The C++ compiler to use
 	CXXFLAGS	Flags to pass to the C compiler
 	LDFLAGS		Flags to pass when linking
@@ -615,6 +617,9 @@ EMACS = emacs --quick
 # Default FLAGS for C compiler (can be overridden by user such as "make CFLAGS=-g")
 CFLAGS = ${CFLAGS}
 
+# Default FLAGS for C preprocessor (can be overridden by user such as "make CPPFLAGS=-I/usr/local/include")
+CPPFLAGS = ${CPPFLAGS}
+
 # Default FLAGS for C++ compiler (can be overridden by user such as "make CXXFLAGS=-g")
 CXXFLAGS = ${CXXFLAGS}