Hadoop 1.0.1 support on Amazon EMR
Depends on whether you are using any specific 1.0.1 classes or not. The core Mapper and Reducer classes (both new and old API types) did not change between 0.20 and 1.0.1.
You can try changing your hadoop dependency to 0.20.2 and re-creating your MR job - if there are no compilation errors, you're pretty close (0.20 to 1.0.1 errors can be fixed, but I imagine you'll be fine).
If you find that your work is not compiled and it belongs to some I / O formats that are not available in 0.20 (like some of the multiple I / O), you might want to check the Hadoop source for 1.0.1 (or even source Cloudera 0.20.2) to see if you can "pass" the missing formats and add them to your work.
Be sure to re-post compilation errors in your original questions so people can comment on potential work.
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