NPE in sstable2json

./sstable2json /var/lib/cassandra/data/test/snapshots/1307649033076/User-g-4-Data.db
{
Exception in thread "main" java.lang.NullPointerException
at org.apache.cassandra.db.ColumnFamily.<init>(ColumnFamily.java:82)
at org.apache.cassandra.db.ColumnFamily.create(ColumnFamily.java:70)
at org.apache.cassandra.io.sstable.SSTableIdentityIterator.<init>(SSTableIdentityIterator.java:142)
at org.apache.cassandra.io.sstable.SSTableIdentityIterator.<init>(SSTableIdentityIterator.java:90)
at org.apache.cassandra.io.sstable.SSTableIdentityIterator.<init>(SSTableIdentityIterator.java:74)
at org.apache.cassandra.io.sstable.SSTableScanner$KeyScanningIterator.next(SSTableScanner.java:179)
at org.apache.cassandra.io.sstable.SSTableScanner$KeyScanningIterator.next(SSTableScanner.java:144)
at org.apache.cassandra.io.sstable.SSTableScanner.next(SSTableScanner.java:136)
at org.apache.cassandra.tools.SSTableExport.export(SSTableExport.java:313)
at org.apache.cassandra.tools.SSTableExport.export(SSTableExport.java:344)
at org.apache.cassandra.tools.SSTableExport.export(SSTableExport.java:357)
at org.apache.cassandra.tools.SSTableExport.main(SSTableExport.java:415)