RewriteMap causing error: not allowed here

Hello.

I tried the following:

     RewriteEngine on
     RewriteMap sessionsTab /home/webadmin/domain.com/html/sessions.txt
     RewriteCond !${sessionsTab:%{REMOTE_ADDR}} =true
     RewriteRule /* /Not_Logged_In.html [R,L]

and get the following error:

    "RewriteMap not allowed here"

I am running Apache 1.3.27 on Linux Redhat 9 in a virtual enviroment (I host more than one domain there, using one IP address).  I have root access.

How can I get rid of the error?


Thanks!