After 9 months, I think you already solved this issue, but I will write my way to solve this.
In your
article.class.php (core/components/articles/model/articles/article.class.php) add a new line after line 276.
$furlTemplate = str_replace('%mycategory', $this->get('tv4'), $furlTemplate);
and replace line 272
$furlTemplate = $this->xpdo->getOption('articleUriTemplate',$settings,'%Y/%m/%d/%alias/');
with this
$furlTemplate = $this->xpdo->getOption('articleUriTemplate',$settings,'%mycategory/%Y/%m/%d/%alias/');
(maybe you dont need to change this)
Note: Change 'tv4' with id of your tv (tv1 or tv3...)
I hope that my post understandable
P.S. It was tested with modx 2.2.8 and articles 1.6.5
With, 2.2.9 i have some problems, but later it was fixed...how i don't know
[ed. note: neehad last edited this post 13 years ago.]