The latest greatest release of Lotus Notes for the Mac, Notes 8.5, only runs on OS X 10.5 (Leopard) on Intel processors.
I can understand why IBM made this the supported configuration, but it does leave users with older software or hardware trying to find out what versions of Notes are open to them. This table might just help:
Notes Client Versions Mac OS Versions Supported Processor Support
(Intel and/or PPC)
Release 8.5 10.5.x
Note: Both standard and basic configurations
of the Notes client on Mac are supported.
(PPC supported with Basic Configuration)
Release 7.0.3 10.5.x (see technote #1290250)
PPC and Intel Release 7.0.2 10.4.x PPC and Intel Release 6.5.6 and 6.5.5 10.4.x
PPC Only Release 6.5.4 10.3.x
PPC Only Release 6.5.3 10.3.x
PPC Only Release 6.5.2 10.3.x
PPC Only Release 6.5 and 6.5.1 10.2.x
- Notes 7.0.2 for Macintosh is the first Notes 7.x release supported on the Mac OS.
- Refer to technote #1290250 for known issues when running Notes 7.0.3 on Mac 10.5.xLink
- Notes 8.5 is the first Notes 8.x release supported on the Mac OS
- Currently there is no 8.0.x version of Notes for the Mac platform; the platforms available for 8.0.x are Linux and Microsoft Windows. Refer to Technote #1265157 for more details.
- For more information on PPC vs. Intel Processor support, seetechnote 1232620 “Is the Intel-based Macintosh a supported platform for Notes“.
Unless you absolutely have no other option, I wouldn’t run any Notes/Mac release older than 7.0.2 – it isn’t a great user experience to say the least, but 7.0.2/7.0.3 are definitely workable solutions for those that need to support older configurations.