I used Matt's solution in topic 16804 to turn WP's XHTML into HTML.
This works fine, but it conflicts when I turn on WP's gzip compression:
Warning: ob_start(): output handler 'ob_gzhandler' cannot be used twice (...)
I also tried adding some lines in .htaccess to turn on gzip compression:
php_value zlib.output_compression 4096
I had the impression this had worked before, but apparently it doesn't work (anymore?) for some reason: no compressed files (XHTML to HTML works fine). Adding the following code also didn't work:
<?php ob_start( 'ob_gzhandler' ); ?>
Is there a way to compress my PHP and HTML files, while still converting XHTML to HTML?