BlackBerry Enterprise Server software version 4.1 Service Pack 5

Interesting, this was kept quite :-| but indeed it is available for download from https://www.blackberry.com/Downloads/entry.do

Service Pack 5

So the release notes say:

Research In Motion (RIM) plans to discontinue support for the “You were BCC’d” portion of messages as of BlackBerry
Enterprise Server Version 5.0 (SDR 79671).
BlackBerry Enterprise Server Version 4.1 SP5 is not certified for use in Japanese environments.
RIM certifies that the BlackBerry Enterprise Server operates on VMware® ESX Server Version 3.0.1. As with any
deployment of the BlackBerry Enterprise Server, consider taking baseline measurements of performance after you
install the BlackBerry Enterprise Server, and then add users in stages to the server. In a VMware environment, other
virtual machines might be running on that server, which might impact how many users the BlackBerry Enterprise
Server can support. See the BlackBerry Enterprise Server Version 4.1 Performance Benchmarking Guide for more
information about performance measurements.
RIM has deemphasized support for BlackBerry® Instant Messaging for Microsoft® Office Live Communications Server
2005 for Windows® Messenger users. RIM does not plan to release new versions of the BlackBerry Instant Messaging
Connector and enterprise instant messaging application for Windows Messenger. BlackBerry Enterprise Server Version
4.1 SP5 and later maintenance releases will continue to include the connector that is compatible with the last release of
the device client only (version 1.1.0.28). The connector will not be included in BlackBerry Enterprise Server Version 5.0
or later.

The Feature and Technical Overview says:

The BlackBerry Enterprise Server now supports the Microsoft SQL Server 2005
(64-bit) database management system.

None of the documents mention anything about Exchange 2007 Service Pack 1 only Exchange 2007!