In case you didn't know, JIRA has a bulk change feature which is really
handy when you need to make the same change to many issues. To use it,
search for the issues that you want to change, and then select Bulk
Change from the Tools menu in the upper right corner. Then select the
ones you want to change (clicking on the box in the column heading
selects all of them), click Next, Select Edit Issues, Next, and then
fill in the form for what you want to change and confirm.
This is handy for cleaning up the issue database in preparation for
evaluating issues for 3.2.
Have fun.
Tom