How can I show the time-left for my users in status.html?

Hello,

We want to show in the $(hostname)/status page the time left for the users until their account expires.
For example, if some users subscribed for a month, in the status page I want to show them how much time they have left in their accounts with something like this:

Time Left: 2w3d23h4m

I have tried many variables to achieve this, here is a sample:
$(input-variable) > output from server in the status.html or alogin.html or test.html–all has the same output.

$(limit-uptime) > $(limit-uptime)

$(session-timeout) > NULL

$(session-timeout-secs) > 0

$(session-valid-till) > $(session-valid-till)

$(idle-timeout) > NULL

$(idle-timeout-secs) > 0

$(uptime) > 1h15m19s

$(rate-limit) > $(rate-limit)

$(keepalive-timeout) > $(keepalive-timeout)

$(session-time-left) > NULL

$(session-time-left-secs) > 0

$(Max-Session-Time) or $(max-session-time) > $(Max-Session-Time) or $(max-session-time)

I used those links as reference while trying the variables above:
http://wiki.mikrotik.com/wiki/Manual:Customizing_Hotspot
http://wiki.mikrotik.com/wiki/Manual:IP/Hotspot
http://www.mikrotik.com/testdocs/ros/3.0/aaa/hotspot.php

The version of Mikrotik server used is 5.16.
Do we need to change some of the server settings?
What are they?
How can we change them?

Thank you.

sooo sorry,i am a fresh bird here!

.up.