This module matches packets based on the application layer data of 
their connections.  It uses regular expression matching to compare 
the application layer data to regular expressions found it the layer7 
configuration files.  This is an experimental module which can be found at 
http://l7-filter.sf.net.  It takes two options.
.TP
.BI "--l7proto " "\fIprotocol\fP"
Match the specified protocol.  The protocol name must match a file 
name in /etc/l7-protocols/ or one of its first-level child directories.
.TP
.BI "--l7dir " "\fIdirectory\fP"
Use \fIdirectory\fP instead of /etc/l7-protocols/.  This option must be 
specified before --l7proto.