Saw the following log during a clean restart of a broker.
2013/01/29 19:18:12.073 INFO [FileMessageSet] [main] [kafka]  Creating or reloading log segment /export/content/kafka/i001_caches/topic1-3/00000000000000000000.log2013/01/29 19:18:12.074 INFO [OffsetIndex] [main] [kafka]  Created index file /export/content/kafka/i001_caches/topic1-3/00000000000000000000.index with maxEntries = 65
5360, maxIndexSize = 10485760, entries = 655360, lastOffset = 0
A couple of things are weird.
1. There are entries in the index, but lastOffset is 0.
2 maxIndexSize/manxEntries = 16, instead of 8.