FreeMarker template error!

Method public java.lang.String info.magnolia.module.ModuleManager$ModuleManagementState.getDeltaTypesDescription(java.lang.String[]) threw an exception when invoked on info.magnolia.module.ModuleManager$ModuleManagementState@7c3422b5
The problematic instruction:
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==> ${status.getDeltaTypesDescription(['installation', 'update', 'installation and update'])} [on line 19, column 26 in info/magnolia/module/ui/ModuleManagerWebUI.header.html]
in include "ModuleManagerWebUI.header.html" [on line 1, column 1 in info/magnolia/module/ui/ModuleManagerWebUI.listTasks.html]
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Java backtrace for programmers:
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freemarker.template.TemplateModelException: Method public java.lang.String info.magnolia.module.ModuleManager$ModuleManagementState.getDeltaTypesDescription(java.lang.String[]) threw an exception when invoked on info.magnolia.module.ModuleManager$ModuleManagementState@7c3422b5
at freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:130)
at freemarker.core.MethodCall._getAsTemplateModel(MethodCall.java:93)
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:209)
at freemarker.core.MixedContent.accept(MixedContent.java:92)
at freemarker.core.Environment.visit(Environment.java:209)
at freemarker.core.Environment.renderElementToString(Environment.java:1568)
at freemarker.core.StringLiteral.getStringValue(StringLiteral.java:101)
at freemarker.core.StringLiteral._getAsTemplateModel(StringLiteral.java:86)
at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
at freemarker.core.Assignment.accept(Assignment.java:90)
at freemarker.core.Environment.visit(Environment.java:209)
at freemarker.core.MixedContent.accept(MixedContent.java:92)
at freemarker.core.Environment.visit(Environment.java:209)
at freemarker.core.Environment.include(Environment.java:1482)
at freemarker.core.Include.accept(Include.java:169)
at freemarker.core.Environment.visit(Environment.java:209)
at freemarker.core.MixedContent.accept(MixedContent.java:92)
at freemarker.core.Environment.visit(Environment.java:209)
at freemarker.core.Environment.process(Environment.java:189)
at freemarker.template.Template.process(Template.java:237)
at info.magnolia.freemarker.FreemarkerHelper.render(FreemarkerHelper.java:148)
at info.magnolia.freemarker.FreemarkerHelper.render(FreemarkerHelper.java:130)
at info.magnolia.module.ui.ModuleManagerWebUI.render(ModuleManagerWebUI.java:154)
at info.magnolia.module.ui.ModuleManagerWebUI.execute(ModuleManagerWebUI.java:86)
at info.magnolia.cms.filters.InstallFilter.doFilter(InstallFilter.java:97)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:82)
at info.magnolia.cms.filters.MgnlFilterChain.doFilter(MgnlFilterChain.java:84)
at info.magnolia.cms.filters.CompositeFilter.doFilter(CompositeFilter.java:66)
at info.magnolia.cms.filters.AbstractMgnlFilter.doFilter(AbstractMgnlFilter.java:88)
at info.magnolia.cms.filters.MgnlMainFilter.doFilter(MgnlMainFilter.java:105)
at info.magnolia.cms.filters.MgnlMainFilter.doFilter(MgnlMainFilter.java:216)
at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1187)
.....
at java.lang.Thread.run(Thread.java:680)
Caused by: freemarker.template.TemplateModelException: Can not unwrap argument [installation, update, installation and update] to [Ljava.lang.String;
at freemarker.ext.beans.SimpleMemberModel.unwrapArgument(SimpleMemberModel.java:132)
at freemarker.ext.beans.SimpleMemberModel.unwrapArguments(SimpleMemberModel.java:120)
at freemarker.ext.beans.SimpleMemberModel.unwrapArguments(SimpleMemberModel.java:98)
at freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:106)
... 70 more