User can't tab out of the "Linked Issues" dropdown field to next item in "Create Issue" form in IE9.

Steps:
1. Goto QA-EACJ and try creating a new issue for sysadmin project.
2.User is using keyboard to move between fields.
3. Once user is in "Linked Issues" dropdown to select issues. Tab again to move to next item.

Result:
1. Nothing happens.
2. User can't click anywhere in form and hence can't do anything.