chan_sip not reading users.conf

G’day all,
Asterisk/SVN-branch-1.6.1-r191783
Asterisk GUI-version : SVN-branch-2.0-r4766

It seems that chan_sip is no longer reading users.conf…
users.conf has about 40 extensions in it and

iax2 show peers shows them all
but sip show peers returns none.

sip show objects returns them all

If I add a manual entry in sip.conf then voiucmail and calling rules work so it looks like its only chan_sip not reading users.conf

Any suggestions?[/i]