In order to be compliant to the accesibility standards,

All the images on the installer must have meaningful alternative text, and the meaning of each image should be consistent within an application.

Here in the installer (Sponsor dialog) there is are few images circulated depending upon the sponsor and that image does not have an alternative text. This alternative text will be used by the Assistive Technologies like JAWS.
Is is Ok to defer this bug for JDK7 with all other accesibility bugs