xtrabackup_logfile exceeds maximum file size given for innodb_log_file_size


Recently I discovered some strange behaviour when running a partial backup with innobackupex. When the backup starts innobackup will create a temporary binary log file during the backup called xtrabackup_logfile which will later be the binlog file. When the cluster is quite busy I’ve seen that this will can grow up to (for example) 3.4GB.
This is a problem, because in the default my.cnf the limit for the log file is 2GB. When you run the apply-log later it will crash with an assertion error like this:

InnoDB: Assertion failure in thread 34892348288 in file pars0pars.cc line 865
InnoDB: Failing assertion: sym_node->table != NULL

I think this makes sense, because the binlog file exceeds the 2GB parameter.
I noticed that the innobackupex doesn’t create more files for the temporary log.
Now I wan’t to try the apply-log with a different default-my.cnf with 4GB for the binary log file.

But the main question is, why does innobackupex doesn’t respect the limits and what if the logfile exceeds the maximum of 4GB? This is the maximum value for MySQL for the innodb_log_file_size parameter.
Hope anyone can help me out or point me in the right direction.

Best regards,