[CCK + Imagefield] 2 ID's for input checkbox

[CCK + Imagefield]
Error occurs when creating new content. Content type contains various sorts of different content, problem when pressing 'update' after browsing for an image. See error message below, browser (correctly) fails to render page.
Firefox message:

XML Parsing Error: duplicate attribute
Location: http://localhost/?q=node/add/content_blog
Line Number 89, Column 151:

Opera thinks:

well-formedness constraint: unique attribute definition
Specification:http://www.w3.org/TR/REC-xml/#uniqattspec

The problem (returns added by me):

<label class="option"><input type="checkbox" name="edit[field_album_cover][0][flags][delete]"
 id="edit-field_album_cover-0-flags-delete" value="1"   
id="field_album_cover-0-delete-checkbox" class="form-checkbox" /> Delete</label>

Opera shows a few more lines: http://pastebin.com/796955

A quick look: In the ImageField module, there's a piece of code between lines 407 and 412 that seem to make up the output.
A quick assumption: the attributes array isn't empty?!

I've built a site a while ago with CCK & Imagefield: worked marvelous. Due to some stupidity I lost all but it wasn't too hard to rebuild it. These errors are new to me but I must point out my system has changed a lot: from Windows XP + XAMPP I went to CentOS 4.4 Linux.
Apache version: Server version: Apache/2.0.52
Server built: Aug 13 2006 03:29:43
PHP version: PHP 4.3.9 (cgi) (built: Sep 21 2006 07:08:09)
Imagefield module: "$Id: imagefield.module,v 1.9.2.1 2006/09/01 22:08:32 dopry Exp $"
Content module: $Id: content.module,v 1.56.2.20 2006/09/19 00:41:42 JonBob Exp $

I apologize in advance if this 'bug' is merely a feat of my own stupidity.