wrong md5 checksum error on drush up

thought i'd report below error received today when i was trying to drush up my d6 install.

Code updates will be made to the following projects: Mailhandler [mailhandler-6.x-2.x-dev], Vote Up/Down [vote_up_down-6.x-2.7]

Note: A backup of your project will be stored to backups directory if it is not managed by a supported version control system.
Note: If you have made any modifications to any file that belongs to one of these projects, you will have to migrate those modifications after updating.
Do you really want to continue with the update process? (y/n): y
<strong>File mailhandler-6.x-2.x-dev.tar.gz is corrupt (wrong md5 checksum).           [error]</strong>
Updating project mailhandler failed. Attempting to roll back to previously     [error]
installed version.
Backups were restored successfully.