Fixed: Customer selection is not translated (bug#10416).
Squashed commit of the following:

commit 467b80b17c59e9b777583717b290a0f6063f528e
Author: s7design <otrs@s7designcreative.com>
Date:   Sat Apr 5 17:57:43 2014 +0200

    [Bug 10416] Customer selection is not translated

    Enable translate in BuildSelection() for Custom user Edit