You want to get dreamweaver to treat .thtml and .ctp files like php files. There are 2 config files that you’ll need to edit
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C:\Documents and Settings\[user]\Application Data\Macromedia\Dreamweaver MX 2004\Configuration\Extensions.txt
PHP,PHP3,PHP4,TPL,THTML,CTP:PHP Files
C:\Program Files\Macromedia\Dreamweaver MX 2004\Configuration\DocumentTypes\MMDocumentTypes.xml
<documenttype id=”PHP_MySQL” servermodel=”PHP MySQL” internaltype=”Dynamic” winfileextension=”php,php3,php4,thtml,ctp” macfileextension=”php,php3,php4,thtml,ctp” file=”Default.php” writebyteordermark=”false”>