I know that there is the option to edit the html source of the content but I rather would like to use a module for this.
So I see two options (correct me if there are more):
Update Joomla to at least version 1.5 (From some forum posts I found out that can be somewhat complicated). I don't know if it is worth the effort since new functionality requirements come rarely (and I think my client doesn't want to pay for a Joomla version update).
Find an appropriate component and leave the old installation as it is.
Can anyone point me into the right direction?