Error occured

Can't use 'defined(%hash)' (Maybe you should just omit the defined()?) at ../lib/jcode.pl line 684.

caller info depth 1

class: JConv
file: (eval 2)
line: 1

caller info depth 2

class: JConv
file: ../lib/JConv.pm
line: 31

caller info depth 3

class: main
file: ../lib/jcode.pl
line: 684

caller info depth 4

class: main
file: ../lib/jcode.pl
line: 684

caller info depth 5

class: CGI::QueryString
file: ../lib/CGI/QueryString.pm
line: 18

caller info depth 6

class: main
file: ../lib/jcode.pl
line: 684