Currently, the only way to retrieve issues that are in a sprint is to do what is suggested here: https://answers.atlassian.com/questions/85039/how-to-filter-by-sprint-now-we-re-using-rapid-boards/85043

So, if you wanted to write your own filter to get back all the issues in a specific sprint, you have to know what all the issues in the sprint are!

The only other way to currently filter is using the following JQL:

Sprint in openSprints()
or
Sprint in closedSprints()

The limitation being that if you have multiple open Sprints, you can't just get back the issues for one of them. If you've closed more than 1 sprint ever, you can't get back the contents of that specific sprint. And if you're planning a sprint, you can't get back anything.

As we Fix Versions in and the 'Classic' way of doing things, where you can use JQL like:

fixVersion = 'Sprint n'

I'd like to be able to do the same with the Sprint field. E.g.

Sprint = 'Sprint n'

Filters are an essential part of how Jira works (especially when used with Dashboards). I'd love to be able to keep using them instead of only relying on the 'Agile' view to get any kind of window into projects managed by GreenHopper.