diff --git a/config/configure.in b/config/configure.in
index a0b38e757..027149191 100755
--- a/config/configure.in
+++ b/config/configure.in
@@ -456,7 +456,7 @@ AC_SUBST(LOCAL_LIBS)
 #--------------------------------------------------
 # Particle Library interface
 #--------------------------------------------------
-BUILD_PARTICLES=
+BUILD_PARTICLES=0
 
 if test "$ENABLE_PARTICLES" = "y"
 then