Not sure if this is xfwm4's fault or xfce4-session's. Anyway, I have an anjuta window and a few Terminal windows that get restored to the 2nd workspace after I start xfce. Everything on the 1st workspace is fine, but if I switch to the second one, I can't focus any of the windows unless I click on the titlebar or borders. After that, they take focus normally if I move to another window and back, but each window needs to have its decorations clicked first. Focus mode (as you might have guessed) is focus-on-click.
I believe it's now fixed in CVS, can you try?
That bug was fixed in RC2 "final"