Forum OpenACS Q&A: adp code not being parsed properly under multiple clause

I can not load AOL Server 3.3 now, since management won't allow me
to play with whatever is already running.

I figured out that the problems start arising whenever i try to
refer a variable inside the multiple tag in adp file. The variable
can be easily used before the multiple tag. Yes the .adp and .tcl pair
rely on the database.

It will be great if you can advice me on how come even the plain
and simple statement like

<if @some_variable@ defined>

  placed after multiple tag inside the adp file lead to variable not
being found. If I am right this should have been translated to the
tcl command

if { info exists ${some_variable} }

  and the action would have proceeded even if the variable was not

Since I am new to both TCL and this entire templating system, and
my background being in C and C++, i am getting altogether more
confused. Any sort of information is welcome. Even if you can tell
me some links to go and read, i would be more than happy doing that,
I just want to make this work.

Thanks Michael Sir for your reply but I am stuck here.