Upgrading to SDK 5.1 gives huge compilation errors

Hi,

We are currently using 5.0 RC SDK. I am trying to upgrade to SDK 5.1. To do this I replaced the vim25.jar present in my project with the latest version. After this I am getting hundreds of compilation errors. Some errors are due to changes in enums like ManagedEntityStatus._green changed to ManagedEntityStatus.GREEN, some are return type changes like getPropSet() (of ObjectContent) return type is changes from DynamicProperty[] to List<DynamicProperty>.

I had few queries:

1. Is there a easy way to resolve all these errors? Any samples provided?
2. Is there any documentation providing mapping between old and new APIs? How do I know get_value() is now value()?
3. After all these changes will I still be able to connect to my old VCs (4.0, 5.0) without any issues? I understand they won't be able to use the new features present in 5.1. Do I need to take care of any compatibility issues?

Thanks,

-Ganesh