diff --git a/acconfig.h b/acconfig.h
index 1045f52024..12ef98bd80 100644
--- a/acconfig.h
+++ b/acconfig.h
@@ -34,6 +34,7 @@ static /**/const char *const rcsid[] = { (char *)rcsid, "\100(#)" msg }
 #undef STRUCT_INODE_HAS_I_TRUNCATE_SEM
 #undef STRUCT_INODE_HAS_I_DIRTY_DATA_BUFFERS
 #undef STRUCT_INODE_HAS_I_MAPPING_OVERLOAD
+#undef STRUCT_INODE_HAS_I_MMAP_SHARED
 #undef STRUCT_ADDRESS_SPACE_HAS_PAGE_LOCK
 
 /* glue for RedHat kernel bug */
diff --git a/configure-libafs.in b/configure-libafs.in
index 210b611b76..40051c6ddd 100644
--- a/configure-libafs.in
+++ b/configure-libafs.in
@@ -118,6 +118,7 @@ case $system in
 		 LINUX_FS_STRUCT_INODE_HAS_I_TRUNCATE_SEM
 		 LINUX_FS_STRUCT_INODE_HAS_I_DIRTY_DATA_BUFFERS
 		 LINUX_FS_STRUCT_INODE_HAS_I_MAPPING_OVERLOAD
+		 LINUX_FS_STRUCT_INODE_HAS_I_MMAP_SHARED
 	  	 LINUX_INODE_SETATTR_RETURN_TYPE
 		 LINUX_NEED_RHCONFIG
 		 LINUX_WHICH_MODULES
@@ -127,6 +128,9 @@ case $system in
 		 if test "x$ac_cv_linux_fs_struct_inode_has_i_dirty_data_buffers" = "xyes"; then 
 		  AC_DEFINE(STRUCT_INODE_HAS_I_DIRTY_DATA_BUFFERS)
 		 fi
+		 if test "x$ac_cv_linux_fs_struct_inode_has_i_mmap_shared" = "xyes"; then 
+		  AC_DEFINE(STRUCT_INODE_HAS_I_MMAP_SHARED)
+		 fi
 		 if test "x$ac_cv_linux_fs_struct_inode_has_i_mapping_overload" = "xyes"; then 
 		  AC_DEFINE(STRUCT_INODE_HAS_I_MAPPING_OVERLOAD)
 		 fi
diff --git a/configure.in b/configure.in
index 9335a9b377..3f64330012 100644
--- a/configure.in
+++ b/configure.in
@@ -118,6 +118,7 @@ case $system in
 		 LINUX_FS_STRUCT_INODE_HAS_I_TRUNCATE_SEM
 		 LINUX_FS_STRUCT_INODE_HAS_I_DIRTY_DATA_BUFFERS
 		 LINUX_FS_STRUCT_INODE_HAS_I_MAPPING_OVERLOAD
+		 LINUX_FS_STRUCT_INODE_HAS_I_MMAP_SHARED
 	  	 LINUX_INODE_SETATTR_RETURN_TYPE
 		 LINUX_NEED_RHCONFIG
 		 LINUX_WHICH_MODULES
@@ -127,6 +128,9 @@ case $system in
 		 if test "x$ac_cv_linux_fs_struct_inode_has_i_dirty_data_buffers" = "xyes"; then 
 		  AC_DEFINE(STRUCT_INODE_HAS_I_DIRTY_DATA_BUFFERS)
 		 fi
+		 if test "x$ac_cv_linux_fs_struct_inode_has_i_mmap_shared" = "xyes"; then 
+		  AC_DEFINE(STRUCT_INODE_HAS_I_MMAP_SHARED)
+		 fi
 		 if test "x$ac_cv_linux_fs_struct_inode_has_i_mapping_overload" = "xyes"; then 
 		  AC_DEFINE(STRUCT_INODE_HAS_I_MAPPING_OVERLOAD)
 		 fi