Screen title not updated in Putty

[cupaxe]

I have been using screen 3.09.15 for a long time now and have had
absolutely no complaints. I use it along with Putty from both my
workplace and at home. Recently, I downloaded screen 4.00.02 and
noticed the following things about it-

1. Ctrl-A \ which used to close all the windows and exit screen
doesn't work anymore
2. The title of the screen window is not shown in Putty.

Has something drastically changed since 3.09.15? I have reverted to
this version but would like to start using 4.00.02.

Any comments are appreciated.

Thanks,
Krishna