diff -ur a/ext/dba/config.m4 b/ext/dba/config.m4
--- a/ext/dba/config.m4	2007-05-18 13:56:52 +0100
+++ b/ext/dba/config.m4	2007-05-18 14:05:28 +0100
@@ -262,6 +262,10 @@
         break
       fi
     done
+	dnl Allow CPPFLAGS to override us if needed.
+	if test "$THIS_PREFIX" = "/usr" && test "$THIS_INCLUDE" = "/usr/include/db.h" ; then
+		THIS_INCLUDE="db.h"
+	fi
     PHP_DBA_DB_CHECK(4, db-4.5 db-4.4 db-4.3 db-4.2 db-4.1 db-4.0 db-4 db4 db, [(void)db_create((DB**)0, (DB_ENV*)0, 0)])
   fi
 ])