Query on Transition Caller Field reports empty results for users with uppercase letter in loginname

Description

Since we upgraded to JIRA6.2.7, we noticed strange behavior with queries using the Transition Caller Field. We have a field called LastIssueCloser, that is filled in the transitions going to "Closed" status in our workflow.
We have a query like "LastIssueCloser is not EMPTY"

It was working fine up when we were using JIRA5 => all issues were reported.

Now that we moved to JIRA6, the same query only provides a subset of the total of issues.
I just found out that issues where the Caller has a username starting with an uppercase letter (which is sometimes the case with our ActiveDirectory) are not taken into account by the query.

This has a strong impact for us, as the results of all queries based on this field (and we have many more of this type) are now completely erroneous, and we cannot generate our reports as the query results are incomplete.

Regards
Gael

Environment

Running in JIRA6.2.7

Customer Info

None

Assignee

Unassigned

Reporter

Gael Neuez

Labels

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Internal Complexity

Unknown

Internal Value

Unknown

Requires documentation

None

Impact

None

Fix versions

Affects versions

Priority

Critical
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