Abstract method error in surefire?

[Benson Margulies]

java.lang.AbstractMethodError:
java.lang.Throwable.getMessage()Ljava/lang/String;
    at
org.apache.maven.surefire.booter.SurefireBooter.runSuitesInProcess(SurefireBooter.java:353)
    at
org.apache.maven.surefire.booter.SurefireBooter.main(SurefireBooter.java:1009)


This 'just started happening.' No additional info from -X.

maven version is 2.2.1.