UNIX for Advanced & Expert Users

My os is sun solaris 8

I have following prompt variable

PS1="`uname -n`$" ; export PS1

this work fine it set the hostname follow by $

but I just installed sudo
and when i issue sudo -s to gain root access
It still set my hostname follow by $
rather than setting hostname follow by #

I tried modifying my .profile so that it includes

UID=`id | awk '{print $1}' | cut -c5`

if [ "$UID" = "0" ]
then
PS1="`uname -n`#" ; export PS1
else
PS1="`uname -n`$" ; export PS1
fi

but this still did not work, when I issue sudo -s
Can you help, Please

Basically, I want to set my prompt variable in my .profile file so that when i sudo -s my PS1 is set
to hostname follow by #