Thanks for the suggestion. I have looked at similar solutions. The reason I am not completely sold on solutions such as CAS and LDAP is largely due to the fact that accounts need to be automatically generated on the 3rd party software side (software such as vBulletin, Mantis). When a user registers on either of our ez Publish sites (Site A or Site B), they must also have access to vBulletin and Mantis.
Therefore, it's not just a single sign-on solution I am looking for, but an account generation / synchronization also.
Please let me know if my proposal falls out of line with best practices, as that is my main concern. Thanks again.