When using pseudo_contains, you probably are executing this pl/sql function once per row in your result set. This function itself is relatively slow and could quite possibly be your bottleneck.
interMedia is an easy alternative to try. For something like ticket tracker, you may want to play with the catalog index type available in Oracle 8.1.7 on. It is useful when you do not need the advanced features of the context index type and when you are indexing small documents. Catalog gives you the benefits of never having to worry about synchronizing your index as they are automatically synchronized at commit time.
http://technet.oracle.com/products/text/x/Tech_Overviews/imt_817.html is a decent overview of the interMedia context and catalog index types along with sample code to get you started.
HTH,
Mike
