Bad implementation of MultipleCompilationErrorsException

ToString method is implemented instead of getMessage in org.codehaus.groovy.control.MultipleCompilationErrorsException class. This breaks the contract of Throwable super class causing silly messages to be printed, when the exception is thrown.
I get this message in my progam:
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Caused by: java.lang.RuntimeException: startup failed
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I changed the implementation which improves the message:
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Caused by: java.lang.RuntimeException: startup failed, groovy.script: 1: unexpected token: > @ line 1, column 24.
1 Error
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