xtrabackup crashes when built against mysql 5.5.29

Tested with xtrabackup 2.0.1, 2.0.5, 2.0.6, all built against MySQL 5.5.29
on a 64bit Ubuntu 12.10 system:

[...]
130322 11:11:10 innobackupex: Starting ibbackup with command: xtrabackup_innodb55 --defaults-group="mysqld" --backup --suspend-at-end --target-dir=/srv/mysqlback/2013-03-22_11-11-08
innobackupex: Waiting for ibbackup (pid=18357) to suspend
[...]
130322 11:11:10 InnoDB: Warning: allocated tablespace 3992, old maximum was 0
>> log scanned up to (784969632874)
innobackupex: Error: ibbackup child process has died at /usr/bin/innobackupex line 381.

from the backtrace i can see that the line that ibbackup
fails on was

Program terminated with signal 11, Segmentation fault.
#0 0x000000008000ee22 in datafiles_iter_next (it=<value optimized out>)
at xtrabackup.c:1006

The corresponding code in xtrabackup.c is:

1006 while (it->space != NULL &&
1007 (it->space->purpose != FIL_TABLESPACE ||
1008 UT_LIST_GET_LEN(it->space->chain) == 0))
1009 it->space = UT_LIST_GET_NEXT(space_list, it->space);

PS: it is a bit weird to see that the innobackupex script still refers to "ibbackup child process"?