Unable to send mail with more than one build definition

here is the trace log

9884077 [pool-1-thread-1] ERROR
org.apache.maven.continuum.notification.ContinuumNotificationDispatcher:default

• Error while trying to use the mail notifier.
  org.codehaus.plexus.notification.NotificationException: INTERNAL
  ERROR: The current build wasn't the first in the build list. Current
  build: '288', first build: '284'.
  at org.apache.maven.continuum.notification.mail.MailContinuumNotifier.getPreviousBuild(MailContinuumNotifier.java:554)
  at org.apache.maven.continuum.notification.mail.MailContinuumNotifier.buildComplete(MailContinuumNotifier.java:241)
  at org.apache.maven.continuum.notification.mail.MailContinuumNotifier.sendNotification(MailContinuumNotifier.java:227)
  at org.apache.maven.continuum.notification.DefaultContinuumNotificationDispatcher.sendNotification(DefaultContinuumNotificationDispatcher.java:199)
  at org.apache.maven.continuum.notification.DefaultContinuumNotificationDispatcher.sendNotification(DefaultContinuumNotificationDispatcher.java:151)

My build has quite a few build definitions running at the same scheduler.
ie builds are serialized