Slight SMF Mod problem

[DavidCT]

Most of you will think this is a stupid thing to want but here it goes.

Long ago I added a "users online" php script to my pages (simular to what is on the bottom of the forum except it just shows how many users, it doesn't know who they are).  It uses MySQL.  When I used PHPBB, it worked fine.  When I added it to SMF it works but gives an error...

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Bottom of forums/index.php I added an "include" to my script.  Also tried adding it to index.template.php or whatever it was called, no luck.

Page loads fine, bottom shows my users online thing, then displays error after all that:

Database Error: Table 'mydbname.smf_sessions' doesn't exist
File: /path.../forums/Sources/Load.php
Line: 2005

I first thought of a $string conflict so I, using "replace" in wordpad (one by one, not automatic) I changed all strings to $uo_stringname (for usersonline) so it can't possibly be a conflict anymore and it still doesn't work.  I don't know anything about SMF or SQL so I figured I'd try to save some time and see if anyone has a clue.  Thanks.