[Orgmode] tab visibility cycling doesn't work over putty/ssh with viper-mode enabled

[Herbert Sitz]

I'm trying to run orgmode/emacs over an ssh connection with PuTTY.  Win7 client
and Ubuntu host.  

With viper-mode enabled all I get is a bell when I click on tab to cycle the
visibility of a heading in viper's normal mode.  

Shift-tab works okay, as does a tab key if I am in viper's insert mode (but of
course it merely inserts tab then rather than cycling visibility).  

Tab cycling seems to work properly if viper-mode is disabled.

I'm new to emacs/orgmode (coming from vim) and to ssh sessions, stumped on this
tab key issue though I suspect it's nothing complicated.  Can someone tell me
how to get tab cycling working in my putty client when using viper-mode?  
Thanks!