Let me take a wild guess...you used a WYSIWYG editor to edit your template pages, right? OR you hacked the template pages and did not properly compare the codes with the original template files, right?
Anyway...as discussed before in this forum and others, you need to have TAGS on separate lines like:
Code:
<%if category%>
<%category%>
<%endif%> -OR- install the
Enhanced Template.pm code hack.
Regards,
Eliot Lee
http://anthrotech.com/