For Single Signon, PeopleSoft supports having Enterprise Portal on a PeopleTools minor release which is equal to or greater than any content providers (e.g. both Enterprise Portal and Financials are on PeopleTools 8.50). In addition, the preferred configuration also has Enterprise Portal on the same or a higher patch as any content provider (e.g. Enterprise Portal on 8.50.09 and Financials on 8.50.03). However, as long as both systems are on the same minor release, SSO is supported, so the content provider could have a higher patch release (e.g. Enterprise Portal on 8.50.03 and Financials on 8.50.09). PeopleSoft does not support the
Enterprise Portal on a lower minor release than the content providers (e.g. Enterprise Portal on PeopleTools 8.49 and Financials on PeopleTools 8.50).
PeopleSoft tests many configurations, but does not test every possible PeopleTools minor release/patch scenario, so any issues found should be reported. Customers who report a Single Signon problem where the Enterprise Portal is on a lower minor release of PeopleTools than a content provider will be required to test on a supported configuration before continuing.
The distinction between 'major' and 'minor' releases can be a bit confusing. Use the following as a general reference:
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Courtesy:http://blogs.oracle.com/peopletools/2010/07/single_sign-on_with_peoplesoft.html