Does the --lock-tables=false option work?
According to the man page, if you are dumping InnoDB tables you can use the --single-transaction option:
--lock-tables, -l
Lock all tables before dumping them. The tables are locked with READ
LOCAL to allow concurrent inserts in the case of MyISAM tables. For
transactional tables such as InnoDB and BDB, --single-transaction is
a much better option, because it does not need to lock the tables at
all.
For innodb DB:
mysqldump --single-transaction=TRUE -u username -p DB