Lotus Notes 8.5.1FP1: Why is ..\com.ibm.rcp.base_6.2.1.20100106-1732\ not used?

As far as I’ve seen is the new base dir installed by 8.5.1 FP1 not used, but the old 8.5.1.The only difference between both version are checkPID.exe and rcplauncher.exe, but I am wondering why the new

…\com.ibm.rcp.base_6.2.1.20100106-1732.… location is not referenced in rcpinstall.properties and rcplauncher.properties.

Using Process Explorer with an Notes 8.5.1 FP1 client, the notes2.exe of the 8.5.1 base dir (6.2.1.20090925-1604) is active, not the one in the appropriate 8.5.1FP1 directory (6.2.1.20100106-1732).

Seen this on all client platforms, including Citrix XenApp 5.0.

This has impact where to change settings…