diff --git a/doc/imapfilter.1 b/doc/imapfilter.1
index e6752dc..ff66c37 100644
--- a/doc/imapfilter.1
+++ b/doc/imapfilter.1
@@ -1,4 +1,4 @@
-.Dd February 19, 2011
+.Dd May 20, 2013
 .Dt IMAPFILTER 1
 .Os
 .Sh NAME
@@ -48,6 +48,9 @@ Enables printing of some brief details of the communication with the server.
 .Bl -tag -width Ds
 .It Ev HOME
 User's home directory.
+.It Ev IMAPFILTER_HOME
+Program's configuration directory, which overrides the default
+.Pa $HOME/.imapfilter/ .
 .El
 .Sh FILES
 .Bl -tag -width Ds