Changing the separator used in autolabel

Hi,

Is it possible to change the separator used in autolabels? For example,
I would like to remove the dot after the chapter number and replace it,
either with a colon or an em space. It is easy to change in the table
of contents, using autotoc.label.separator but I would also like to
have the same separator in my chapter titles and in the header of the
fo version of my book.

Thanks in advance.

Diane Larin

INRO