You can see this for yourself with the following command line:
curl -A "Mozilla/5.0 (iPhone; U; OS X Leopard 9A365; en) KHTML" https://qa29.longsight.com/portal/scripts/portalscripts.js
Or, you can use Safari and set your user agent to iOS and then go directly to the url.
I think folks haven't noticed this before because mobile users are usually first sent to /portal/pda. If they choose to "opt-out" and back into the standard portal, a preference is set, so requests for /portal/scripts/portalscripts.js after that "opt out" are fine.
For folks that use a non-standard portal, like say, xsl-portal, there is already an apache redirect in place to send requests from /portal to /xsl-portal, so they bypass the "opt-out" button and so get the "redirected" js file.