--- zerofree-1.0.1.old/sparsify.c	2012-01-16 14:15:53.752724537 +0000
+++ zerofree-1.0.1/sparsify.c	2012-01-16 14:27:18.546285148 +0000
@@ -43,8 +43,9 @@
 
 		if ( i == fs->blocksize && !p->dryrun ) {
 			ext2fs_unmark_block_bitmap(fs->block_map, *blocknr) ;
-			group = ext2fs_group_of_blk(fs, *blocknr);
-			fs->group_desc[group].bg_free_blocks_count++;
+			group = ext2fs_group_of_blk2(fs, *blocknr);
+			ext2fs_bg_free_blocks_count_set(fs, group,
+				ext2fs_bg_free_blocks_count(fs, group) + 1);
 			fs->super->s_free_blocks_count++ ;
 			/* the inode counts blocks of 512 bytes */
 			p->inode->i_blocks  -= fs->blocksize / 512 ;