sorting does not work when reading and writing docs at the same time

[kRyszard]

using solandra with cassandra 1.0.5 (commit 5dd17c8 grimesp authored December 12, 2011), using org.apache.cassandra.dht.ByteOrderedPartitioner, using schema with field type: name="long" class="solr.LongField" omitNorms="true", using this field type in field: name="post_orig_id" type="long" indexed="true" stored="true" required="true" .

performing a query:
http://localhost:8983/solandra/idxPosts.global1/select?q=_:_&rows=50000&sort=post_orig_id+asc&fl=post_orig_id

sorting is ok, but when performing the query again and simultaneously adding new documents then the result is not ordered.