cannot open job-config page in IE8 when using groovy-postbuild plugin

Groovy-postbuild plugin is a great work, thanks !
However, the trouble below has occurred in our Jenkins since I wrote a experimental job using this plugin.

When someone tries to open any job-config page of any job in IE8, IE8 raises a javascript error as follows:

No Object, Line: 812, Character: 29, Code: 0
URI: http://ourjenkins/ourPrefix/static/4b0b67f3/scripts/hudson-behavior.js

   "TR.row-set-end": function(e) { // see rowSet.jelly and optionalBlock.jelly
        // figure out the corresponding start block
        var end = e;

        for( var depth=0; ; e=e.previousSibling) { ## here ##

Sorry if I'm wrong and if it's a FAQ, but

• When disabled this plugin, we can open job config page in IE8
• Other Jenkins without this plugin works well in IE8
• No trouble at least when using Firefox and Chrome browsers

So I suppose this plugins affects some outputs (ex. javascript and/or html) to browsers, and IE8 is sensitive? to them.