rsync says some files can not be transferred

Hi,
I just used rsync to copy over a larg file set, at the end of the
session, rsync prints out the following,

sent 16 bytes received 2975988 bytes 1219.42 bytes/sec
total size is 6402302674 speedup is 2151.31
rsync error: some files could not be transferred (code 23) at
/home/lapo/packaging/tmp/rsync-2.6.6/main.c(1173)

I use command line like this, "rsync -a -vv <src> <dst>", it is
double "v" in the command to see more debug message.

The problem is it does not tell me what files are not transfered over.

Any pointer?

Thanks,
Jibin

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