Compression and Cache conflict?

Hello,

i have this issue. Im running CentOS Linux server and there are many wordpress sites hosted and two phpbb forums and other sites.

What i want to do is to enable content precompression on server. But im afraid this thing.

Some of my wordpresses have W3 Total Cache plugin installed and my PHPBB forums has gzip compression enabled.

What will hapen when i enable it in addition globaly on server (httpd.conf)? Any conflict?

<IfModule mod_deflate.c>
    <IfModule mod_setenvif.c>
        BrowserMatch ^Mozilla/4 gzip-only-text/html
        BrowserMatch ^Mozilla/4\.0[678] no-gzip
        BrowserMatch \bMSIE !no-gzip !gzip-only-text/html
        BrowserMatch \bMSI[E] !no-gzip !gzip-only-text/html
    </IfModule>
    <IfModule mod_headers.c>
        Header append Vary User-Agent env=!dont-vary
    </IfModule>
    AddOutputFilterByType DEFLATE text/css application/x-javascript text/html text/richtext image/svg+xml text/plain text/xsd text/xsl text/xml image/x-icon
</IfModule>
<FilesMatch "\.(css|js)$">
    FileETag None
    <IfModule mod_headers.c>
         Header set X-Powered-By "W3 Total Cache/0.9.1.3"
    </IfModule>
</FilesMatch>
<FilesMatch "\.(html|htm|rtf|rtx|svg|svgz|txt|xsd|xsl|xml)$">
    FileETag None
    <IfModule mod_headers.c>
         Header set X-Powered-By "W3 Total Cache/0.9.1.3"
    </IfModule>
</FilesMatch>
<FilesMatch "\.(asf|asx|wax|wmv|wmx|avi|bmp|class|divx|doc|docx|exe|gif|gz|gzip|ico|jpg|jpeg|jpe|mdb|mid|midi|mov|qt|mp3|m4a|mp4|m4v|mpeg|mpg|mpe|mpp|odb|odc|odf|odg|odp|ods|odt|ogg|pdf|png|pot|pps|ppt|pptx|ra|ram|swf|tar|tif|tiff|wav|wma|wri|xla|xls|xlsx|xlt|xlw|zip)$">
    FileETag None
    <IfModule mod_headers.c>
         Header set X-Powered-By "W3 Total Cache/0.9.1.3"
    </IfModule>
</FilesMatch>

-------------------------------

<IfModule mod_deflate.c>
SetOutputFilter DEFLATE

<IfModule mod_setenvif.c>
# Netscape 4.x has some problems…
BrowserMatch ^Mozilla/4 gzip-only-text/html

# Netscape 4.06-4.08 have some more problems
BrowserMatch ^Mozilla/4\.0[678] no-gzip

# MSIE masquerades as Netscape, but it is fine
BrowserMatch \bMSIE !no-gzip !gzip-only-text/html

# NOTE: Due to a bug in mod_setenvif up to Apache 2.0.48
# the above regex won’t work. You can use the following
# workaround to get the desired effect:
#BrowserMatch \bMSI[E] !no-gzip !gzip-only-text/html

# Don’t compress already-compressed files
SetEnvIfNoCase Request_URI .(?:gif|jpe?g|png)$ no-gzip dont-vary
SetEnvIfNoCase Request_URI .(?:exe|t?gz|zip|bz2|sit|rar)$ no-gzip dont-vary
SetEnvIfNoCase Request_URI .(?:avi|mov|mp3|mp4|rm|flv|swf|mp?g)$ no-gzip dont-vary
SetEnvIfNoCase Request_URI .pdf$ no-gzip dont-vary
</IfModule>

<IfModule mod_headers.c>
# Make sure proxies don’t deliver the wrong content
Header append Vary User-Agent env=!dont-vary
</IfModule>
</IfModule>