--- Makefile.PL.orig	2013-05-31 14:09:56.468100782 +0200
+++ Makefile.PL	2013-05-31 14:11:13.104848616 +0200
@@ -53,9 +53,11 @@
 
 if( length $apxs ) {
   warn "# Using apxs at $apxs\n";
+  my ($inc)  =qx/$apxs -q INCLUDEDIR/;
   my ($extra)=qx/$apxs -q EXTRA_INCLUDES/;
+  chomp $inc;
   chomp $extra;
-  push @ARGV, "INC=$extra"
+  push @ARGV, "INC=-I$inc $extra"
 } else {
   die "Could not figure out which apxs to use. Try the -apxs option.\n";
 }