log seq # in ibdata files do not match the log seq number nnn in the ib_logfiles!

Took a full backup and executing prepare command getting error “ibdata files do not match the log sequence number xxxx in the ib_logfiles!”

why the sequence number mismatch reported?

--------------- command and log ------------
$ innobackupex --apply-log --redo-only /backup/mysql-innobackupex1/full1

InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy
and Percona LLC and/or its affiliates 2009-2013. All Rights Reserved.

This software is published under
the GNU GENERAL PUBLIC LICENSE Version 2, June 1991.

IMPORTANT: Please check that the apply-log run completes successfully.
At the end of a successful apply-log run innobackupex
prints “completed OK!”.

131112 01:09:15 innobackupex: Starting ibbackup with command: xtrabackup_56 --defaults-file=“/backup/mysql-innobackupex1/full1/backup-my.cnf” --defaults-group=“mysqld” --prepare --target-dir=/backup/mysql-innobackupex1/full1 --apply-log-only --tmpdir=/tmp

xtrabackup_56 version 2.1.5 for MySQL server 5.6.11 Linux (x86_64) (revision id: 680)
xtrabackup: cd to /backup/mysql-innobackupex1/full1
xtrabackup: This target seems to be not prepared yet.
xtrabackup: xtrabackup_logfile detected: size=2097152, start_lsn=(1634832)
xtrabackup: using the following InnoDB configuration for recovery:
xtrabackup: innodb_data_home_dir = ./
xtrabackup: innodb_data_file_path = ibdata1:10M:autoextend
xtrabackup: innodb_log_group_home_dir = ./
xtrabackup: innodb_log_files_in_group = 1
xtrabackup: innodb_log_file_size = 2097152
xtrabackup: using the following InnoDB configuration for recovery:
xtrabackup: innodb_data_home_dir = ./
xtrabackup: innodb_data_file_path = ibdata1:10M:autoextend
xtrabackup: innodb_log_group_home_dir = ./
xtrabackup: innodb_log_files_in_group = 1
xtrabackup: innodb_log_file_size = 2097152
xtrabackup: Starting InnoDB instance for recovery.
xtrabackup: Using 104857600 bytes for buffer pool (set by --use-memory parameter)
InnoDB: The InnoDB memory heap is disabled
InnoDB: Mutexes and rw_locks use GCC atomic builtins
InnoDB: Compressed tables use zlib 1.2.3
InnoDB: Using CPU crc32 instructions
InnoDB: Initializing buffer pool, size = 100.0M
InnoDB: Completed initialization of buffer pool
InnoDB: Highest supported file format is Barracuda.
InnoDB: The log sequence numbers 1625987 and 1625987 in ibdata files do not match the log sequence number 1634832 in the ib_logfiles!
InnoDB: Database was not shutdown normally!
InnoDB: Starting crash recovery.

InnoDB: Reading tablespace information from the .ibd files…
InnoDB: Restoring possible half-written data pages
InnoDB: from the doublewrite buffer…
InnoDB: Last MySQL binlog file position 0 761, file name mysql-bin.000003

[notice (again)]
If you use binary log and don’t use any hack of group commit,
the binary log position seems to be:
InnoDB: Last MySQL binlog file position 0 761, file name mysql-bin.000003

xtrabackup: starting shutdown with innodb_fast_shutdown = 1
InnoDB: Starting shutdown…
InnoDB: Shutdown completed; log sequence number 1634832
131112 01:09:16 innobackupex: completed OK!