getting a ksh variable value

Hi everybody!
I need some help with this...
I have those 3 variables defined on ksh:

VAR=TONTO
NUM=1
TONTO1=OK

I'd like to obtain TONTO1's value but using VAR and NUM.

If I do:

echo ${VAR${NUM}}

It returns (on HP UX):

sh: ${VAR${NUM}}: The specified substitution is not valid for this command.

You will need to use eval but be aware that this leads to tricky syntax especially with complex commands.

eval echo \$${VAR}${NUM}

This makes ksh parse the command twice. On the first pass the backslash stops ksh from trying to expand the following $, but the backslash is removed. Also on the first pass, ${VAR} and ${NUM} are expanded.

On the second pass, it looks like:
echo $TONTO1