.htaccess & dreamhost - error combining two parts [solved]

[eluser]Diggory Laycock[/eluser]
Hi,
Sorry, yet another .htaccess issue - I was hoping someone could help me figure out what I'm doing wrong.

Here's the scenario:
I've got a standard htaccess format that I use for my codeigniter sites that normally works very well: e.g.

Code:

<IfModule mod_rewrite.c>
    Options +FollowSymLinks
    RewriteEngine on
    RewriteBase /~diggory/someCodeIgniterSiteNameHere/
    RewriteCond $1 !^(index\.php|public|user_guide|robots\.txt)
    RewriteRule ^(.*)$ index.php/$1 [QSA,L]
</IfModule>

I've been using this on a site I've had in development for a client. The site is hosted at DreamHost, and while in development the site was hidden in a subdirectory of the web root: i.e. http://www.myclient.com/staging/ and it was all working well.

The site allows the client to upload his own videos. DreamHost's default php.ini has a relatively small max_upload - so in order to allow the client to upload larger videos I had to place an .htaccess file in the web root of the site which runs php files with a custom php wrapper as per this page: http://wiki.dreamhost.com/index.php/PHP.ini

Code:

Action php-cgi /cgi-bin/php-wrapper.cgi
Action php5-cgi /cgi-bin/php-wrapper.cgi

That all worked well - and the upload limit was enlarged as per my custom php.ini

However - once the site was to go live - the codeingiter directory became the same as the web root - so I need to combine these two .htaccess files. I assumed I could just combine them as so:

Code:

Action php-cgi /cgi-bin/php-wrapper.cgi
Action php5-cgi /cgi-bin/php-wrapper.cgi

<IfModule mod_rewrite.c>
    Options +FollowSymLinks
    RewriteEngine on
    RewriteBase /
    RewriteCond $1 !^(index\.php|public|user_guide|robots\.txt)
    RewriteRule ^(.*)$ index.php/$1 [QSA,L]
</IfModule>

Alas - this doesn't appear to work - if I use either of them on their own they work - but if I combine the directives into one file I get the following:

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, <email removed> and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

Additionally, a 500 Internal Server Error error was encountered while trying to use an ErrorDocument to handle the request.

I'm a bit mystified by why this should happen.

Has anyone got any ideas? Thanks.