If JIRA would allow me to create an actual hierarchy of issues (not just sub-tasks, it should go down to sub-sub-sub-sub...tasks), then it will have everything I need for Requirements Management in JIRA

The features I would need are:

• ability to set "parent" issue when creating an issue
• ability to view Project issues as a tree
• automatic issue resolution when all child issues are resolved

Example of issue hierarchy:

+ ROOT Issue (Type: User requirement): Manage Customers
+ Child Issue (Type: Technical Requirement): Ability to Create Customers
+ Child Issue (Type: Task): Dialog for entering customer data
+ Child Issue (Type: Task): Dialog for entering customer data
+ Child Issue (Type: Technical requirement): Edit Customers
+ Child Issue (Type: Technical requirement): Delete Customers
....