Browser prompts me to download the index.php3 file

Hi, I have a Cobalt Qube3 (includes php-4.0.1-C7q3) with the following apache settings: httpd.conf: LoadModule php4_module modules/libphp4.so AddModule mod_php4.c srm.conf: AddType application/x-httpd-php4 .php .php3 I added the .php3 to the AddType line in an attempt to get Horde (http://www.horde.org) and IMP (http://www.horde.org/imp) to work. When I browse to the URL I get prompted to download the index.php3 file. I know the Qube3 comes with its own WebMail solution, but I'm trying to get IMP working on this box as a facility for another mail server. I also don't want to mess with the Qube's config too much (i.e. I don't want to have to rebuild apache and php as the box is still under warranty). Other things I have tried: Renaming the .php3 files to .php - the scripts insist that setup.php(3) is readable. Not so! I think this is a php<3 problem and the message is a red herring, but I'm not sure. Can anyone help? Many thanks Derek