I used this one http://svg.codeplex.com/ and I am quite satisfied with it. Still has some bugs so you should have a look at the patches in http://svg.codeplex.com/SourceControl/PatchList.aspx.
When I discover mistakes I can solve I post them directly there. But it takes some time to be evaluated by the guys there. It's a better idea to have a look at the patches and apply them yourself.
The library is reasonably sufficient for most usual needs. for really fancy stuff, it needs to be improved thought...
