1.8.2 upgrade.php wants include.php to be writable

[kendo451]

Upgrading from CMSMS 1.8.1 to 1.8.2 I am encountering an unusual problem that causes checksums to fail.  (System info posted at the end).

1. Setup: download cmsms 1.8.2 base version and untar it via shell. I untar it, change ownership to the correct user, and set tmp, uploads, modules and config.php to 775/664 so they are all writable by apache.

2. Go to mysite/install/upgrade.php, view the license agreement and click next.

3. I get this error:
Write permission is required for .../include.php

4. If I change include.php to 664, then I can continue, but that file will fail the checksum test.

Any idea why the upgrade script is writing to include.php?

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