Nope. Just export it out as Parasolid and re-import it in 2011.
You will lose the feature tree, but you get the geometry. Using SolidWorks direct editing tools like split, move/copy, combine, move face, offset face and so on, you can modify the model in 2011 with ease.
If you have SolidWorks Professional or Premium, you can also use the FeatureWorks to attempt to identify and recreate features.
You can save as a Parasolid, the file will not be parametric but you will be able to open in previous versions. If you have Featureworks you can try and reconstruct the feature tree.