Remaining 6u31 java plugin and java webstart are not being registered at all

With the sequence of install and install jre ,fx2.1, the remaining 6u31 java plugin is not registered with all browswer: FF, IE, GC. Also, javaws.exe is gone from /system32

**** Tested Config:
- x86 Win7 (uac off)
- jre 6u29, 6u31-b04, 7u4-b09, fx 2.1 (b10 promotion or latest deploy-scrum bit)
- Browsers FF 6.0.2, IE 8, GC 16.x

*** Steps to reproduce:
0) Make sure no jre or javafx runtime on the system. All java related registries clean
1) Install 6u29 (fcs)
2) Install JavaFX 2.1 runtime (latest b10 promotion) or latest latest deploy-scrum bit at:
http://jfx.sfbay.sun.com/hudson/view/2.1/job/2.1-deploy-scrum/ (tested with latest b36)

3) Install 7u4-b09 (latest promotion)
4) Install 6u31-b04 (latest promotion)
5) Uninstall 7u4
6) Uninstall FX 2.1

At this point, the system still has 6u31-b04 registered but all the browsers *IE, GC.,FF) does NOT register 6u31 java plug-in at all. No plug-in used by any browser
Also, no javaws.exe under /system32