diff --git a/sparsify-opaque-group-desc.patch b/sparsify-opaque-group-desc.patch
new file mode 100644
index 0000000..2db49f9
--- /dev/null
+++ b/sparsify-opaque-group-desc.patch
@@ -0,0 +1,14 @@
+--- 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 ;
diff --git a/zerofree.spec b/zerofree.spec
index 32e9f9d..c1b05b7 100644
--- a/zerofree.spec
+++ b/zerofree.spec
@@ -1,7 +1,7 @@
 Summary:        Utility to force unused ext2 inodes and blocks to zero
 Name:           zerofree
 Version:        1.0.1
-Release:        9%{?dist}
+Release:        10%{?dist}
 License:        GPL+
 Group:          System Environment/Libraries
 
@@ -16,6 +16,10 @@ Source2:        http://intgat.tigress.co.uk/rmy/uml/index.html
 Source3:        zerofree.sgml
 Source4:        zerofree.8
 
+# e2fsprogs >= 1.42 prevents you from accessing the block group
+# descriptor struct directly.
+Patch1:         sparsify-opaque-group-desc.patch
+
 URL:            http://intgat.tigress.co.uk/rmy/uml/
 
 BuildRequires:  e2fsprogs-devel
@@ -40,6 +44,7 @@ should be careful.
 %setup -q
 cp -p %{SOURCE1} .
 cp -p %{SOURCE2} .
+%patch1 -p1
 
 
 %build
@@ -68,6 +73,9 @@ rm -rf $RPM_BUILD_ROOT
 
 
 %changelog
+* Mon Jan 16 2012 Richard W.M. Jones <rjones@redhat.com> - 1.0.1-10
+- Patch sparsify to work with e2fsprogs >= 1.42.
+
 * Sat Jan 14 2012 Fedora Release Engineering <rel-eng@lists.fedoraproject.org> - 1.0.1-9
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_17_Mass_Rebuild