Velocity Problem after QB update #2630

We updated our QB from 5.0x to 5.1.1
After the update, the evaluation of velocity templates fails


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#set( $Link = ${vars.get("ParentBuildID")} )
<table width="100%" cellspacing="1" cellpadding="5" border="0"  >
<tr bgcolor="99C1DB" >
<td valign="top" ><a style="text-decoration: none;" target="_blank" href="$system.url/build/$Link/scm_changes">
<font size="3" color="000000">Zu den Perfocre Änderungen, des zugehörigen  Elternknotens, <b>($configuration.parent)</b></font></a>
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</tr>
</table>
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Error Message

14:05:07,296 TRACE - Velocimacro : initialization starting.
14:05:07,296 DEBUG - Velocimacro : "velocimacro.library" is not set. Trying default library: VM_global_library.vm
14:05:07,296 DEBUG - Velocimacro : Default library not found.
14:05:07,296 DEBUG - Velocimacro : allowInline = true : VMs can be defined inline in templates
14:05:07,296 DEBUG - Velocimacro : allowInlineToOverride = false : VMs defined inline may NOT replace previous VM definitions
14:05:07,296 DEBUG - Velocimacro : allowInlineLocal = false : VMs defined inline will be global in scope if allowed.
14:05:07,296 DEBUG - Velocimacro : autoload off : VM system will not automatically reload global library macros
14:05:07,296 TRACE - Velocimacro : Velocimacro : initialization complete.
14:05:07,296 TRACE - RuntimeInstance successfully initialized.
14:05:07,296 INFO  - Executing post-execute action...
14:05:07,296 ERROR - Step 'master>Composition-SCM-Link>Misc-Create-SCM-Changes-Link' is failed: Failed to evaluate Velocity template.
14:05:07,296 TRACE - Stack trace for the failure
    com.pmease.quickbuild.QuickbuildException: Failed to evaluate Velocity template. 
        at com.pmease.quickbuild.util.ExceptionUtils.wrapException(ExceptionUtils.java:89) 
        at com.pmease.quickbuild.plugin.basis.TemplateEvalStep.run(TemplateEvalStep.java:84) 
        at com.pmease.quickbuild.plugin.basis.TemplateEvalStep$$EnhancerByCGLIB$$7b1b3c73.CGLIB$run$0(<generated>) 
        at com.pmease.quickbuild.plugin.basis.TemplateEvalStep$$EnhancerByCGLIB$$7b1b3c73$$FastClassByCGLIB$$f468f0d8.invoke(<generated>) 
        at net.sf.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:215) 
        at com.pmease.quickbuild.DefaultScriptEngine$Interpolator.intercept(DefaultScriptEngine.java:270) 
        at com.pmease.quickbuild.plugin.basis.TemplateEvalStep$$EnhancerByCGLIB$$7b1b3c73.run(<generated>) 
        at com.pmease.quickbuild.stepsupport.Step.execute(Step.java:508) 
        at com.pmease.quickbuild.stepsupport.StepExecutionJob.executeStepAwareJob(StepExecutionJob.java:30) 
        at com.pmease.quickbuild.stepsupport.StepAwareJob.executeBuildAwareJob(StepAwareJob.java:47) 
        at com.pmease.quickbuild.BuildAwareJob.execute(BuildAwareJob.java:61) 
        at com.pmease.quickbuild.grid.GridJob.run(GridJob.java:71) 
        at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) 
        at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source) 
        at java.util.concurrent.FutureTask.run(Unknown Source) 
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source) 
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) 
        at java.lang.Thread.run(Unknown Source) 
    Caused by: java.lang.NullPointerException: logTag (i.e. template name) cannot be null, you must provide an identifier for the content being evaluated 
        at org.apache.velocity.runtime.RuntimeInstance.evaluate(RuntimeInstance.java:1291) 
        at org.apache.velocity.runtime.RuntimeInstance.evaluate(RuntimeInstance.java:1265) 
        at org.apache.velocity.app.VelocityEngine.evaluate(VelocityEngine.java:199) 
        at com.pmease.quickbuild.plugin.basis.TemplateEvalStep.run(TemplateEvalStep.java:80) 
        ... 16 more
14:05:07,491 INFO  -

could it be due to the update?

Georg