Variables disappeared

[Libero Spagnolini]

Hi. It seems I lost a lot of internal variables but I cannot figure out 
why. The last thing I've done was setting the variable 
ps-even-or-odd-pages to odd-page and nothing went wrong; for instance I 
used to have a lot of variables beginning with ps- now I got only 3. 
Using C-h v and looking for all the variables beginning with 'ps-' I get:

Possible completions are:
ps-line-number                     ps-multibyte-buffer
ps-paper-type

Anyone can help?
I want my variables back!

Bye

Libe