Using an Admin Account to Access Multiple Mailboxes
Other Java-Exchange connectors use MAPI and impersonation to access the Exchange Server. The motivation behind using impersonation is to be able to access multiple mailboxes without the need for special admin privileges. Although this is a feasible solution, it has been known to cause some problems. As Microsoft points out:
"We've seen a number of crashes in code that uses impersonation and then uses MAPI. Many of these relate to heap allocations occurring with one user context and then the deallocations happening with another context. Both the Exchange and Outlook development teams are aware of these issues. However, especially due to the problem with CreateThread, we've not been able to fix all of them."
Source: http://blogs.msdn.com/stephen_griffin/archive/2005/04/13/407925.aspx
Microsoft's suggested solution for accessing multiple mailboxes is to use an admin account instead of impersonation:
"If you're using impersonation in order to access multiple mailboxes, you may be doing too much work. […]code running under an administrator account with the right permissions […] can access any mailbox without doing any impersonation."
Source: http://blogs.msdn.com/stephen_griffin/archive/2005/04/13/407925.aspx
The technology used by J-Integra for Exchange to access multiple mailboxes is akin to what Microsoft recommends. As pointed out in this knowledge base article, we require the use of an admin account when accessing multiple mailboxes.