ModeShape requires CND files be in the JCR 2.0 format, and result in errors when some pre-JCR 2.0 CND files are used. To make it as easy as possible for people migrating from Jackrabbit to ModeShape, ModeShape should support reading in the older-style CND formats.

The CND format was originally defined by the Jackrabbit project and was not standardized until JCR 2.0. And when it was standardized, there were a few minor changes to the format:
1) Child node definitions should use the SNS keyword rather than the older MULTIPLE keyword (though the meaning is identical and thus they are technically interoperable)
2) Child node definitions should use the PRIMARYITEM keyword rather than just "PRIMARY". Again, no semantic difference.

Our CND importer has a boolean flag that defines whether pre-JCR 2.0 CND formats are allowed, and this is currently set to 'false'. To support JR-style CND formats, this flag should be set to 'true'.