JIRA 4.4 introduced a possible NullPointerException in the DefaultWatcherManager

The following line in the DefaultWatcherManager may throw a NullPointerException due to Autoboxing in JIRA 4.4:

if (issue.getLong("watches") == 0)

Normally the "watches" field should be populated in the database, however for historical reasons it could well be null in which case this line will throw a NPE.