Pig does not work on DateType

cqlsh:PigDemo> describe columnfamily test1897;

CREATE COLUMNFAMILY test1897 (
KEY text PRIMARY KEY,
testcol timestamp
) WITH
comment='' AND
comparator=text AND
row_cache_provider='SerializingCacheProvider' AND
key_cache_size=200000.000000 AND
row_cache_size=0.000000 AND
read_repair_chance=1.000000 AND
gc_grace_seconds=864000 AND
default_validation=blob AND
min_compaction_threshold=4 AND
max_compaction_threshold=32 AND
row_cache_save_period_in_seconds=0 AND
key_cache_save_period_in_seconds=14400 AND
replicate_on_write=True;

cqlsh:PigDemo> select * from test1897;
KEY | testcol
----+------------------------
akey | 2012-01-21 00:14:12+0000

$ cat test1897.pig
cassandra_data = LOAD 'cassandra://PigDemo/test1897' USING CassandraStorage() AS (name, columns: bag

);
dump cassandra_data;

there seems problem with the DateType. the above simple pig script fail with the attached err