The identifier $eval() returns an error message when trying to evaluate a variable that has a single parenthesis in its name.
Example:
Join any channel with a single parenthesis in its name, like '#test(test'.
In the channel editbox, paste (without the quotation marks) '//var -s %test $+ # value | echo -a $eval($+(%,test,#),2)' and press enter.
The script should return 'value', instead it returns this error 'Invalid format: $evalnext'.
I'm using mIRC 6.03 with windows 98.