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http://confluence.atlassian.com/display/JIRA/JIRA+4.0+Release+Notes
http://confluence.atlassian.com/display/JIRA/JIRA+4.1+Release+Notes http://confluence.atlassian.com/display/JIRA/JIRA+4.2+Release+Notes
Searching
- Advanced searching now supports something called Jira Query Language (JQL) which allows greater control over how you find issues.
Dashboard
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Highlights of JIRA 4.0:
Advanced Searching
Dashboard Gadgets
Activity Streams
New-look "Browse Project"
Charting Now Comes Standard
New-look Header
Issue Actions in the Issue Navigator
Project Icons
Default Unit for Time Tracking
"History" is now permanent
NEW - Industry standard OpenSocial Gadgets can be added to dashboards. Out of the box there are 29 different gadgets that can be added these include a variety of charts and reports.
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