Autocomplete - get list of filtered results

Autocomplete - get list of filtered results

Is there a way to 'fetch' the results of a filtered list?
eg. list contains
cat, catalog, catalogue, catalogues
If I type in catalog, the list should just show the last three items.
Is there some clean programmatic way to fetch the results of the filter, short of using the filter as a regex on the source list (in a hidden variable in my case).
[So, I still don't know how to get this done, but the regex method works good enough for the moment - maybe I haven't come across a rainy day test case yet...]

Related to this, if I remove items from the autocomplete, the autocomplete continues to show them, eventhough firebug shows that the source list has been modified - do I need to detach and reattach the autocomplete for it to show the changes - or how would I do this? If I refresh the page, then the modified list shows correctly.
Apologies if I posted to the wrong forum.
[So, this problem and the following problem appear to have the same answer - the 'live' thing. After doing this things are working well now]

Just want to add one more thing - if I setup an autocomplete on a pageload, it works fine. If I try to create a 'dynamic' autocomplete - eg. inside a div created on the fly, the autocomplete doesn't work - any tips on how to do this would be appreciated

[So consider this issue closed]