--- configure
+++ configure
@@ -2383,7 +2383,7 @@
   withval="$with_netpbm"
    if test "$withval" != "no"; then
     LDFLAGS="-L$withval/lib $LDFLAGS";\
-    CPPFLAGS="-I$withval/include $CPPFLAGS";\
+    CPPFLAGS="-I$withval/include/netpbm $CPPFLAGS";\
    fi
 fi;
 if test -n "$with_netpbm"; then echo "option: with_netpbm $with_netpbm"; fi