Unable to create userPageName with space

xWiki supports spaces in page names for users. However when specifying a userPageName format in xwiki.cfg, this does not seem possible.

xWiki-created user page URL;

xWiki-created user xwikidoc entry;

I have attempted defining as follows

xwiki.authentication.ldap.userPageName=${ldap.givenName} ${ldap.sn}

However the space is removed upon page creation. I have also attempted enclosing the parameter with quotes, double quotes and replacing the space with %20 as experiments, but they are all taken literally.

I believe the authenticator should be able to create user pages with spaces, as this is valid in xWiki for users.