■ Present Behavior

On the issue details page, in the "All" tab (for example), entries are associated with timestamps that appear as English phrases:

Chip added a comment - 2009-08-27 09:54 AM
Dale made changes - 2010-01-12 07:24 PM

In Japanese, they appear as:

Chip がコメント - 2009-08-27 09:54 午前 を追加
Dale が - 2010-01-12 07:24 午後 を変更

The grammar of these Japanese-language phrases is incorrect.

■ Desired Behavior

The correct grammar is:

Chip がコメント - 2009-08-27 09:54 午前 に追加
Dale が - 2010-01-12 07:24 午後 に変更

and, within this context, the fully-intelligible and therefore recommended form is:

Chip がコメント - 2009-08-27 09:54 午前 に追加しました
Dale が - 2010-01-12 07:24 午後 に変更しました

• • The desired change is the "を" → "に", and adding "しました" to the end of the phrase.

■ Steps to reproduce

0. Sign in to JIRA, ensure the user's locale is set to Japanese.
1. View an issue whose "All" history presents items that have undergone both "Added" and "Edited" operations.
2. Observe the present behavior

よろしくお願いします。