Cannot compile jclouds with Guava 21+

/home/gaul/work/jclouds/core/src/main/java/org/jclouds/rest/internal/TransformerForRequest.java:102: error: method compose in interface java.util.function.Function<T,R> cannot be applied to given types;
         transformer = compose(Function.class.cast(wrappingTransformer), transformer);
                       ^
  required: java.util.function.Function<? super V,? extends HttpRequest>
  found:    com.google.common.base.Function,com.google.common.base.Function<HttpResponse,CAP#1>
  reason: cannot infer type-variable(s) V
    (actual and formal argument lists differ in length)
  where V,T,R are type-variables:
    V extends Object declared in method <V>compose(java.util.function.Function<? super V,? extends T>)
    T extends Object declared in interface java.util.function.Function
    R extends Object declared in interface java.util.function.Function
  where CAP#1 is a fresh type-variable:
    CAP#1 extends Object from capture of ?
/home/gaul/work/jclouds/core/src/main/java/org/jclouds/rest/internal/TransformerForRequest.java:189: error: method compose in interface java.util.function.Function<T,R> cannot be applied to given types;
            transformer = compose(new OnlyElementOrNull(), transformer);
                          ^
  required: java.util.function.Function<? super V,? extends HttpRequest>
  found:    OnlyElementOrNull,com.google.common.base.Function<HttpResponse,CAP#1>
  reason: cannot infer type-variable(s) V
    (actual and formal argument lists differ in length)
  where V,T,R are type-variables:
    V extends Object declared in method <V>compose(java.util.function.Function<? super V,? extends T>)
    T extends Object declared in interface java.util.function.Function
    R extends Object declared in interface java.util.function.Function
  where CAP#1 is a fresh type-variable:
    CAP#1 extends Object from capture of ?