Reading the changes in OTRS 4.0.7, I was surprised to see this:

MySQL: Added check for innodb_log_file_size setting to both the installer and the support data collector in order to make sure it matches the minimum requirements.

MySQL's documentation shows that:
innodb_log_file_size * innodb_log_files_in_group = <redo log size>

So OTRS should be checking both settings:
innodb_log_file_size * innodb_log_files_in_group >= 512 MB

Furthermore, the MySQL documentation shows that the redo log is (only?) used for crash recovery:
http://dev.mysql.com/doc/refman/5.6/en/glossary.html#glos_redo_log

So what inspired this check in the first place?

And if the check is really needed, perhaps it should be added to otrs.CheckDB.pl, together with some information in the installation and upgrade manual.

Alan