javascript - strange behavior in jQuery validation plugin -

hi using jquery version 1.6.2 , jquery validation plugin 1.5.2 ,

i have custom validator

jquery.validator.addmethod("venue_type", function(value, element) {     if(value>0){return true;}else{return false;} }, "venue type required"); 

to check dropdown value selected .

i have form called venue_edit_form

<form id="venue_edit_form" class="venue_edit_form"     directory_id="<?php echo $venue_details->directoryid; ?>">  //code    </form> 

i have added jquery validation form

jquery('#venue_edit_form').validate({     rules:{         venuename:{             required:true,             minlength:1,             maxlength:50         },         venuedescription :{             required:false,             lettersonly:true,             maxlength:150         }     },     messages:{         venuename: {             required:"venue name required",             minlength:"minimum 1  character required",             maxlength:"venue name should not exceed 50 characters"         },          venuedescription:{                               maxlength:"description should not exceed 150 characters"         }     } }); 

i validate venue name , description , when validate form strange thing append.

an error coming did not validate drop down in edit form , check source

there custom attribute in save button called venue_type

i surprised , changed custom validater name

jquery.validator.addmethod("venue_type_validater", function(value, element) {     if(value>0){return true;}else{return false;} }, "venue type required"); 

now working fine ,

why custom attribute gave error, thought jquery validation plugin validates field name.

is bug ????

please tell me happening .

thanks in advance .

if @ following code validation plugin, makes use of attributerules also

    var data = $.validator.normalizerules(     $.extend(         {},         $.validator.classrules(element),         $.validator.attributerules(element),         $.validator.datarules(element),         $.validator.staticrules(element)     ), element); 

in attributerules if attribute in element matches rules name rule applied element

try

jquery('#venue_edit_form').validate({     ignore: ':hidden, #venue_edit_save',     rules:{         venuename:{             required:true,             minlength:1,             maxlength:50         },         venuedescription :{             required:false,             lettersonly:true,             maxlength:150         }     },     messages:{         venuename: {             required:"venue name required",             minlength:"minimum 1  character required",             maxlength:"venue name should not exceed 50 characters"         },          venuedescription:{                               maxlength:"description should not exceed 150 characters"         }     } });