upper letter at the end of the subject is recognised as small

[tborisova]

I have email with this subject: Unsubscription from mailing list of Retiffy. I am using open_email(@instance1.owner.email,:with_subject => "Unsubscription from mailing list of Retiffy") and my test is failing with:
Could not find email With subject "Unsubscription from mailing list of retiffy".
Found the following emails:
Subject: Unsubscription from mailing list of Retiffy'

Does anyone had the same problem? I am using rails 3.0.9 and ruby 1.9.2-p290