The most current version of MyODBC at the original time of writing was 2.50.28. The current version is 2.50.37-1, the following points refer to the .28 build.
If you wish to use a earlier version of MyODBC then avoid 2.50.26, this had problem in the configure script and build that caused it to not produce a shared object. As the driver manager requires a shared object this was a bit of a problem :-)
I have used 2.50.24 with success, but if you want to be up to date, then build MyODBC 2.50.28 after applying the patch, and then build with the 2.23 client libs. This also works fine.
We are hoping in the near future to have some RPM's built that contain all these fixes and will remove the need to have the non stable release on your system.