Subversion and IPCop
Although the squid proxy supports WebDAV, subversion uses some non-standard methods that squid blocks.
For example, trying to check out a module fails:
svn: REPORT request failed on '/svn/mojain/!svn/vcc/default' svn: REPORT of '/svn/mojain/!svn/vcc/default': 400 Bad Request (http://...)
Adding the following lines to squid.conf (which on IPCop 1.4.6 is located at /etc/squid/squid.conf) allows svn to work:
extension_methods request REPORT extension_methods request MKACTIVITY extension_methods request CHECKOUT extension_methods request MERGE
You need to restart squid for this to take effect: