RIM put together a great page on comparing BES 4.1 SP6 with BES 5.0 for both Exchange and Domino.

For those of you that are contemplating the upgrade ... or will be contemplating the upgrade it is worth a read. Be sure to take note of all the features that require handheld OS 5.0; which we'll hopefully see before the end of the year.

Check it out: BlackBerry - Enterprise Server Compare - Microsoft Exchange - IBM Lotus Domino

I know a few people that either use or want to get into using Wi-Fi enabled BlackBerry handhelds ... this one is for them.

Plus, anything I can do to take the bottleneck off of my carrier's network makes me happy ... my Wi-Fi is as good if not better than any mobile 3G out there.

Check it out ...

KB13922 - System requirements and support for Wi-Fi enabled BlackBerry smartphones

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Jeez ... more Domino. That said, I've actually used this and worked with customers to implement it.

No chit chat on this one, just the goods:

KB10460 - How to configure address book lookups between different IBM Lotus Domino domains

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• BlackBerry® Enterprise Server version 4.1 SP2 to 4.1 SP6 for IBM® Lotus® Domino®

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So, for me I always recommend reboots of a BlackBerry Enterprise Server when there is a scheduled restart / failover of an Exchange or Global Catalog server (heck, BES needs both to work!). Unfortunately, not everyone can do this, and reboots / restarts / failovers aren't always planned.

BES isn't an Exchange cluster-aware application, so it can't effectively handle failovers like we'd all want it to ... well at least until Exchange 2010 (aka E14) is released and then with all MAPI...

This is actually an awesome KB article. It mostly only applies to people using the NA NOC ... but still a good read. Frankly, I never tell anyone to use a proxy for BES SRP connectivity (mostly because it adds another layer of complexity to something that people already don't usually understand) ... but if you're using / need to proxy SRP connections, here are two supportable ways to do it:

KB19236 - Recommended configuration for SRP connections through a proxy ...