Fqn node = Fqn.fromString("/a");
TransactionManager tm1 = cache1.getConfiguration().getRuntimeConfig().getTransactionManager();
TransactionManager tm2 = cache2.getConfiguration().getRuntimeConfig().getTransactionManager();
tm1.begin();
cache1.put(node, "k", "v-older");
Transaction t1 = tm1.suspend();
tm2.begin();
cache2.put(node, "k", "v-newer");
tm2.commit();