InnoDB tables which names contain *opt*, *par*, *CSV*, *MYD* and so on backed up twice

Output of innobackupex:

sudo innobackupex --no-lock --stream=xbstream ~/test-1 > ~/test-4.xbm
[sudo] password for raghu:

InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy
and Percona Inc 2009-2012. All Rights Reserved.

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

120427 10:14:47 innobackupex: Starting mysql with options: --unbuffered --
120427 10:14:47 innobackupex: Connected to database with mysql child process (pid=5816)
120427 10:14:53 innobackupex: Connection to database server closed
IMPORTANT: Please check that the backup run completes successfully.
           At the end of a successful backup run innobackupex
           prints "completed OK!".

innobackupex: Using mysql Ver 14.14 Distrib 5.5.21, for Linux (x86_64) using readline 5.1
innobackupex: Using mysql server version Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.

innobackupex: Created backup directory /home/raghu/test-1
120427 10:14:53 innobackupex: Starting mysql with options: --unbuffered --
120427 10:14:53 innobackupex: Connected to database with mysql child process (pid=5846)
120427 10:14:55 innobackupex: Connection to database server closed

120427 10:14:55 innobackupex: Starting ibbackup with command: xtrabackup_55 --backup --suspend-at-end --target-dir=/tmp/ --stream=xbstream
innobackupex: Waiting for ibbackup (pid=5854) to suspend
innobackupex: Suspend file '/tmp//xtrabackup_suspended'

xtrabackup_55 version 2.0.0 for Percona Server 5.5.16 Linux (x86_64) (revision id: 417)
xtrabackup: uses posix_fadvise().
xtrabackup: cd to /var/lib/mysql
xtrabackup: Target instance is assumed as followings.
xtrabackup: innodb_data_home_dir = /var/lib/mysql
xtrabackup: innodb_data_file_path = ibdata1:10M:autoextend
xtrabackup: innodb_log_group_home_dir = /var/lib/mysql
xtrabackup: innodb_log_files_in_group = 2
xtrabackup: innodb_log_file_size = 5242880
120427 10:14:55 InnoDB: Using Linux native AIO
xtrabackup: using O_DIRECT
120427 10:14:55 InnoDB: Warning: allocated tablespace 66, old maximum was 9
>> log scanned up to (1492855886)
[01] Streaming /var/lib/mysql/ibdata1
[01] ...done
[01] Streaming ./testxbm/lolopt.ibd
[01] ...done
[01] Streaming ./xyz/dtrpg_products_to_sites.ibd
[01] ...done
[01] Streaming ./xyz/products.ibd
[01] ...done
[01] Streaming ./xyz/products_description.ibd
[01] ...done
[01] Streaming ./test/items.ibd
[01] ...done
[01] Streaming ./test/t.ibd
[01] ...done
[01] Streaming ./test/testp#P#p0.ibd
[01] ...done
[01] Streaming ./test/stk_styleVal.ibd
[01] ...done
[01] Streaming ./test/stk_styleItem.ibd
[01] ...done
[01] Streaming ./i22429/handle22.ibd
[01] ...done
[01] Streaming ./i22429/handle6.ibd
[01] ...done
[01] Streaming ./i22429/handle16.ibd
[01] ...done
[01] Streaming ./i22429/handle21.ibd
[01] ...done
[01] Streaming ./i22429/handle10.ibd
[01] ...done
[01] Streaming ./i22429/handle8.ibd
[01] ...done
[01] Streaming ./i22429/handle15.ibd
[01] ...done
[01] Streaming ./i22429/handle3.ibd
[01] ...done
[01] Streaming ./i22429/handle12.ibd
[01] ...done
[01] Streaming ./i22429/handle7.ibd
[01] ...done
[01] Streaming ./i22429/handle4.ibd
[01] ...done
[01] Streaming ./i22429/handle13.ibd
[01] ...done
[01] Streaming ./i22429/handle9.ibd
[01] ...done
[01] Streaming ./i22429/handle14.ibd
[01] ...done
[01] Streaming ./i22429/handle20.ibd
[01] ...done
[01] Streaming ./i22429/handle2.ibd
[01] ...done
[01] Streaming ./i22429/handle1.ibd
[01] ...done
[01] Streaming ./i22429/handle5.ibd
[01] ...done
[01] Streaming ./i22429/handle23.ibd
[01] ...done
[01] Streaming ./i22429/handle18.ibd
[01] ...done
[01] Streaming ./i22429/data.ibd
[01] ...done
[01] Streaming ./i22429/handle17.ibd
[01] ...done
[01] Streaming ./i22429/handle19.ibd
[01] ...done
[01] Streaming ./i22429/handle11.ibd
[01] ...done
[01] Streaming ./test1/t1.ibd
[01] ...done
[01] Streaming ./test1/t2.ibd
[01] ...done

120427 10:14:59 innobackupex: Continuing after ibbackup has suspended
120427 10:14:59 innobackupex: Starting mysql with options: --unbuffered --
120427 10:14:59 innobackupex: Connected to database with mysql child process (pid=5868)
>> log scanned up to (1492855886)

120427 10:15:01 innobackupex: Starting to backup .frm, .MRG, .MYD, .MYI,
innobackupex: .TRG, .TRN, .ARM, .ARZ, .CSM, .CSV and .opt files in
innobackupex: subdirectories of '/var/lib/mysql'
innobackupex: Backing up file '/var/lib/mysql/testxbm/db.opt'
innobackupex: Backing up file '/var/lib/mysql/testxbm/lolopt.frm'
innobackupex: Backing up file '/var/lib/mysql/testxbm/lolopt.ibd'
innobackupex: Backing up file '/var/lib/mysql/xyz/db.opt'
innobackupex: Backing up file '/var/lib/mysql/xyz/products_to_sites_sales.MYI'
innobackupex: Backing up file '/var/lib/mysql/xyz/products_description.frm'
innobackupex: Backing up file '/var/lib/mysql/xyz/products_to_sites_sales.MYD'
innobackupex: Backing up file '/var/lib/mysql/xyz/dtrpg_products_to_sites.frm'
innobackupex: Backing up file '/var/lib/mysql/xyz/products_to_sites_sales.frm'
innobackupex: Backing up file '/var/lib/mysql/xyz/products.frm'
innobackupex: Backing up file '/var/lib/mysql/test/t.frm'
innobackupex: Backing up file '/var/lib/mysql/test/t1.frm'
innobackupex: Backing up file '/var/lib/mysql/test/testp.par'
innobackupex: Backing up file '/var/lib/mysql/test/items.frm'
innobackupex: Backing up file '/var/lib/mysql/test/testp.frm'
innobackupex: Backing up file '/var/lib/mysql/test/t2.frm'
innobackupex: Backing up file '/var/lib/mysql/test/stk_styleItem.frm'
innobackupex: Backing up file '/var/lib/mysql/test/stk_styleVal.frm'
innobackupex: Backing up files '/var/lib/mysql/performance_schema/*.{frm,MYD,MYI,MRG,TRG,TRN,ARM,ARZ,CSM,CSV,opt,par}' (18 files)
innobackupex: Backing up files '/var/lib/mysql/mysql/*.{frm,MYD,MYI,MRG,TRG,TRN,ARM,ARZ,CSM,CSV,opt,par}' (72 files)
innobackupex: Backing up files '/var/lib/mysql/t2/*.{frm,MYD,MYI,MRG,TRG,TRN,ARM,ARZ,CSM,CSV,opt,par}' (12 files)
innobackupex: Backing up files '/var/lib/mysql/i22429/*.{frm,MYD,MYI,MRG,TRG,TRN,ARM,ARZ,CSM,CSV,opt,par}' (25 files)
innobackupex: Backing up file '/var/lib/mysql/test1/db.opt'
innobackupex: Backing up file '/var/lib/mysql/test1/t1.frm'
innobackupex: Backing up file '/var/lib/mysql/test1/t2.frm'
120427 10:15:02 innobackupex: Finished backing up .frm, .MRG, .MYD, .MYI, .TRG, .TRN, .ARM, .ARZ, .CSV, .CSM and .opt files

innobackupex: Resuming ibbackup

xtrabackup: The latest check point (for incremental): '1492855886'
xtrabackup: Stopping log copying thread.
.>> log scanned up to (1492855886)

xtrabackup: Streaming transaction log from a temporary file...
xtrabackup: Done.
xtrabackup: Transaction log of lsn (1492855886) to (1492855886) was copied.
120427 10:15:03 innobackupex: Connection to database server closed

innobackupex: Backup created in directory '/home/raghu/test-1'
120427 10:15:03 innobackupex: completed OK!

Which cause failure when xbstream extracting backup:

mkdir ~/test-4; cat ~/test-4.xbm | xbstream -v -x -C ~/test-4
backup-my.cnf
ibdata1
./testxbm/lolopt.ibd
./xyz/dtrpg_products_to_sites.ibd
./xyz/products.ibd
./xyz/products_description.ibd
./test/items.ibd
./test/t.ibd
./test/testp#P#p0.ibd
./test/stk_styleVal.ibd
./test/stk_styleItem.ibd
./i22429/handle22.ibd
./i22429/handle6.ibd
./i22429/handle16.ibd
./i22429/handle21.ibd
./i22429/handle10.ibd
./i22429/handle8.ibd
./i22429/handle15.ibd
./i22429/handle3.ibd
./i22429/handle12.ibd
./i22429/handle7.ibd
./i22429/handle4.ibd
./i22429/handle13.ibd
./i22429/handle9.ibd
./i22429/handle14.ibd
./i22429/handle20.ibd
./i22429/handle2.ibd
./i22429/handle1.ibd
./i22429/handle5.ibd
./i22429/handle23.ibd
./i22429/handle18.ibd
./i22429/data.ibd
./i22429/handle17.ibd
./i22429/handle19.ibd
./i22429/handle11.ibd
./test1/t1.ibd
./test1/t2.ibd
testxbm/db.opt
testxbm/lolopt.frm
xbstream: Can't create/write to file './testxbm/lolopt.ibd' (Errcode: 17)
xbstream: failed to create file.