On line 18869 of the configure script, it checks that the ant version is >= 1.7. It uses some kind of string comparison. This breaks for my current ant version (1.10). It seems to think that 1.10 is not >= 1.7. I think this is because it's comparing strings without taking into account what the strings actually mean. Something like this might be a possible patch:
This should be fixed because it means that people with new ant versions can't build the java thrift library.
Also it should be checked to see if other parts of the configure process are using these kinds of faulty version checks.