COPYRIGHT_TEXT=<a href="http://www.psoft.net"><font face="helvetica,verdana,arial" size="1">Copyright 2002. Positive Software Corporation. All rights reserved</font></a>
Then restart SiteStudio.
1. There are two masonry.properties files in SiteStudio. One is used for SiteStudio itself (it's located in psoft_config directory), another one is for SiteStudio on-line demo (located in the demo/WEB-INF/classes/psoft_config directory). So, if you want to change copyright for both modes, you need to changes both of the mentioned files.
2. COPYRIGHT_TEXT cannot be empty, so if you don't want any text for it, just insert html char.