Solr spellchecking fails on sharded query

[Eric Wilson]

I have a Solr application that is distributed into 11 shards, using Solr
version 4.0.0.2011.07.26.16.34.16

In the solrconfig.xml for each shard, I have configured a spellcheck
component:

    <searchComponent name="spellcheck" class="solr.SpellCheckComponent">

      <str name="queryAnalyzerFieldType">textSpell</str>

      <lst name="spellchecker">

        <str name="name">cn_spell</str>

        <str name="field">company_name_spell</str>

        <float name="threshold">0.0001</float>

        <str name="buildOnOptimize">true</str>

        <str name="spellcheckIndexDir">./spellchecker_cn_spell</str>

      </lst>

    </searchComponent>

I have built the dictionary for each shard, and verified that each shard
will return suggestions for misspellings. Moreover, it is evident that a
different dictionary is being used for the various shards.

The problem comes when I submit a sharded query. In that case the result
comes back with the following:

    <lst name="spellcheck">
      <lst name="suggestions"/>
    </lst>

In other words, the list of words for which there are suggestions is empty.

Is there a trick to sharded spellchecking? I appreciate any suggestions.

Eric