You can create an index on the Meta field and change the sql in the
search script to search just that field.
Use something like this to create the index:
texis -s -d .../webinator/db "create metamorph index xhmeta on html(Meta)"
Then change the SQL statements in the search script to search "Meta" instead
of "Title\Meta\Body" .
You'll need to issue the same "create metamorph index ..." command as above
after each walk as gw only updates the default indices.
You might want to include the document title too. In that case change
"Meta" to "Title\Meta" in the above description.