QUOTE (Igor Sereda @ May 18, 2010)

If you need to see all bugs blocked by a single bug X, you can open bug X and in the details view click on the "magnifying glass" icon near the "blocks" field.
Unfortunately this often doesn't work if you have a lot of bugs blocking your chosen one, instead you just get a subset and an error message "Cannot run query (Server HTTP response [414 Request-URI Too Large])
Even if you can return all the blocking bugs you can't add the nice "create distribution" sub-filters as you can with a regular query. I voted for
http://jira.almworks.com/browse/DZO-845 which I think is the intuitive fix.
If there is anything I can do to help move that along, let me know.
Thanks
Charles