diff --git a/documentation/content/en/books/handbook/firewalls/_index.adoc b/documentation/content/en/books/handbook/firewalls/_index.adoc
--- a/documentation/content/en/books/handbook/firewalls/_index.adoc
+++ b/documentation/content/en/books/handbook/firewalls/_index.adoc
@@ -1283,7 +1283,7 @@
 
 [NOTE]
 ====
-Transitioning from userland man:natd[8] to in-kernel NAT might seem seamless at first but there is small catch. When using the GENERIC kernel, IPFW will load the [.filename]#libalias.ko# kernel module, when `firewall_nat_enable` is enabled in [.filename]#rc.conf#. The [.filename]#libalias.ko# kernel module only provides basic NAT functionality, whereas the userland implementation man:natd[8] has all NAT functionality available in its userland library without any extra configuration. All functionality refers to the following kernel modules that can additionally be loaded when needed besides the standard [.filename]#libalias.ko# kernel module: [.filename]#alias_cuseeme.ko#, [.filename]#alias_ftp.ko#, [.filename]#alias_bbt.ko#, [.filename]#skinny.ko#, [.filename]#irc.ko#, [.filename]#alias_pptp.ko# and [.filename]#alias_smedia.ko# using the `kld_list` directive in [.filename]#rc.conf#. If a custom kernel is used, the full functionality of the userland library can be compiled in, in the kernel, using the `options LIBALIAS`.
+Transitioning from userland man:natd[8] to in-kernel NAT might appear seamless at first but there is small catch. When using the GENERIC kernel, IPFW will load the [.filename]#libalias.ko# kernel module, when `firewall_nat_enable` is enabled in [.filename]#/etc/rc.conf#. The [.filename]#libalias.ko# kernel module only provides basic NAT functionality, whereas the userland implementation man:natd[8] has all NAT functionality available in its userland library without any extra configuration. All functionality refers to the following kernel modules that can additionally be loaded when needed besides the standard [.filename]#libalias.ko# kernel module: [.filename]#alias_ftp.ko#, [.filename]#alias_bbt.ko#, [.filename]#skinny.ko#, [.filename]#irc.ko#, [.filename]#alias_pptp.ko# and [.filename]#alias_smedia.ko# using the `kld_list` directive in [.filename]#/etc/rc.conf#. If a custom kernel is used, the full functionality of the userland library can be compiled in, in the kernel, using the `options LIBALIAS`.
 ====
 
 ==== Port Redirection