Index: firmware/common/disk.c
===================================================================
--- firmware/common/disk.c	(revision 22871)
+++ firmware/common/disk.c	(working copy)
@@ -68,7 +68,7 @@
 struct partinfo* disk_init(IF_MD_NONVOID(int drive))
 {
     int i;
-    unsigned char sector[512];
+    unsigned char sector[SECTOR_SIZE];
 #ifdef HAVE_MULTIDRIVE
     /* For each drive, start at a different position, in order not to destroy 
        the first entry of drive 0. 
Index: firmware/export/fat.h
===================================================================
--- firmware/export/fat.h	(revision 22871)
+++ firmware/export/fat.h	(working copy)
@@ -26,7 +26,9 @@
 #include "mv.h" /* for volume definitions */
 #include "config.h"
 
+#ifndef SECTOR_SIZE
 #define SECTOR_SIZE 512
+#endif
 
 /* Number of bytes reserved for a file name (including the trailing \0).
    Since names are stored in the entry as UTF-8, we won't be able to