Compilation failed due to Name clash

I am using SmarGWT version 4.0, GWT version 2.6 and Java 1.7.0_45 on MAC OSX 10.9.2

I am getting following compilation error -

gwtc:
[java] Compiling module de.dimetis.linkmanager.LinkManager
[java] Validating units:
[java] [ERROR] Errors in 'jar:file:/Users/X/Documents/SOURCES/BRANCH_DEV_2014/thirdparty/gwt/smartgwt/smartgwtpower.jar!/com/smartgwt/client/bean/types/EnumValueType.java'
[java] [ERROR] Line 26: Name clash: The method registerValueType(Class<T>) of type EnumValueType<ValueType> has the same erasure as registerValueType(Class<T>) of type OtherValueType<ValueType> but does not hide it
[java] [ERROR] Errors in 'jar:file:/Users/X/Documents/SOURCES/BRANCH_DEV_2014/thirdparty/gwt/smartgwt/smartgwtpower.jar!/com/smartgwt/client/bean/types/JsoValueType.java'
[java] [ERROR] Line 31: Name clash: The method registerValueType(Class<T>) of type JsoValueType<ValueType> has the same erasure as registerValueType(Class<T>) of type OtherValueType<ValueType> but does not hide it
[java] [ERROR] Aborting compile due to errors in some input files

BUILD FAILED

Please suggest ...