Expression commit.author is undefined in notification email

2016-07-13 21:56:42,335 ERROR [AtlassianEvent::0-BAM::EVENTS:pool-1-thread-15] [runtime] Expression commit.author is undefined on line 35, column 3 in notification-templates/notificationCommonsText.ftl.

Expression commit.author is undefined on line 35, column 3 in notification-templates/notificationCommonsText.ftl.
The problematic instruction:
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==> ${commit.author.fullName} [on line 35, column 1 in notification-templates/notificationCommonsText.ftl]
 in user-directive showCommits [on line 7, column 1 in notification-templates/BuildMissingCapableAgentTextEmail.ftl]
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Java backtrace for programmers:
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freemarker.core.InvalidReferenceException: Expression commit.author is undefined on line 35, column 3 in notification-templates/notificationCommonsText.ftl.
	at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
	at freemarker.core.TemplateObject.invalidTypeException(TemplateObject.java:134)
	at freemarker.core.Dot._getAsTemplateModel(Dot.java:78)
	at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
	at freemarker.core.Expression.getStringValue(Expression.java:93)
	at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
	at freemarker.core.Environment.visit(Environment.java:210)
	at freemarker.core.MixedContent.accept(MixedContent.java:92)
	at freemarker.core.Environment.visit(Environment.java:210)
	at freemarker.core.IteratorBlock$Context.runLoop(IteratorBlock.java:167)
	at freemarker.core.Environment.visit(Environment.java:417)
	at freemarker.core.IteratorBlock.accept(IteratorBlock.java:102)
	at freemarker.core.Environment.visit(Environment.java:210)
	at freemarker.core.MixedContent.accept(MixedContent.java:92)
	at freemarker.core.Environment.visit(Environment.java:210)