[TYPO3-ttnews] tt_news 2.5.2 Removing the comma , that is in between multiple categories

[aaron kenez]

Hello

I have a news list that looks like this
<li class="###NEWS_CATEGORY###">
When I assign multiple categories to a news article I get this
<li class="cat1, cat2">
I want to know how to remove comma , so I get the class to look like this
<li class="cat1 cat2">
I was hoping that someone would know if there was some typoscript or another
method to do this.
Thank you.