problem of CS5 Indesign

I've been using CS4 Indesign... as i set the master pages.
it was fine when i do the book.
However when the file got edited by CS5, issue appear.

in CS4 Indesign file,
pg 1 applied Master A
pg 2, & 3 (left side applied None master, rigth side Master B)
pg 4 applied Master D

However, in CS 5, when we tried to edit, it become
pg 1 applied Master A
pg 2, & 3 (left side got Forced to show with Master B on the pg, rigth side Master B)
pg 4 applied Master D

as the planning, the pg 2 supposed to show with None master, but know it forces me to show the Master B on the page.... Does anyone know how i can fix it when i am using CS5?



Please advise~~~
thanks thanks

G'day

You should be able to just click-drag the "none" master and drop it on page 2.

m.

yea.. that's what i did.. but on my junior's file, when i try to apply different master just on page 2, it force me to apply it in a spread, but not in single page.
i dont know why.
~_~"