Exception when null component lead notified of issue change

The following situation results in a NullPointerException
1. Components exist in the system which do not have a "Component Lead" value set
2. A notification scheme exists that makes use of the "Component Lead" notification
3. An issue is updated in a manner that results in the "Component Lead" being notified

The resulting stacktrace is attached in the file "stacktrace.txt"

A quick glance would suggest that there may be a problem somewhere near:
com.atlassian.jira.notification.type.enterprise.ComonentLead - getRecipients(IssueEvent event, String argument)

• which is where a NotificationRecipient is created with a null User