diff -ruN courier-authlib-0.59.1.orig/authuserdb.c courier-authlib-0.59.1/authuserdb.c
--- courier-authlib-0.59.1.orig/authuserdb.c	2006-10-29 05:22:52 +1000
+++ courier-authlib-0.59.1/authuserdb.c	2007-01-28 00:49:47 +1000
@@ -82,14 +82,14 @@
 		return (-1);
 
 	userdb_set_debug(courier_authdebug_login_level);
-	userdb_init(USERDB ".dat");
+	userdb_init(USERDB ".db");
         if ( (u=userdb(cci.user)) == 0)
 	{
 		userdb_close();
 		return (-1);
 	}
 
-	if ( (udbs=userdbshadow(USERDB "shadow.dat", cci.user)) == 0)
+	if ( (udbs=userdbshadow(USERDB "shadow.db", cci.user)) == 0)
 	{
 		free(u);
 		userdb_close();
diff -ruN courier-authlib-0.59.1.orig/authuserdbpwd.c courier-authlib-0.59.1/authuserdbpwd.c
--- courier-authlib-0.59.1.orig/authuserdbpwd.c	2006-10-29 05:22:52 +1000
+++ courier-authlib-0.59.1/authuserdbpwd.c	2007-01-28 00:49:47 +1000
@@ -254,7 +254,7 @@
 	struct  userdbs *udb;
 
 
-	udbs=userdbshadow(USERDB "shadow.dat", uid);
+	udbs=userdbshadow(USERDB "shadow.db", uid);
 
 	if (!udbs)
 	{
@@ -305,7 +305,7 @@
 	free(passwords);
 	free(udbs);
 
-        userdb_init(USERDB ".dat");
+        userdb_init(USERDB ".db");
         if ( (u=userdb(uid)) == 0 ||
 	     (udb=userdb_creates(u)) == 0)
         {
diff -ruN courier-authlib-0.59.1.orig/preauthuserdbcommon.c courier-authlib-0.59.1/preauthuserdbcommon.c
--- courier-authlib-0.59.1.orig/preauthuserdbcommon.c	2006-10-29 05:22:52 +1000
+++ courier-authlib-0.59.1/preauthuserdbcommon.c	2007-01-28 00:49:47 +1000
@@ -35,7 +35,7 @@
 int	rc;
 
 	userdb_set_debug(courier_authdebug_login_level);
-	userdb_init(USERDB ".dat");
+	userdb_init(USERDB ".db");
 	/* We rely on DPRINTF doing 'safe' printing */
 	DPRINTF("userdb: looking up '%s'", userid);
         if ( (u=userdb(userid)) == 0)
@@ -63,7 +63,7 @@
 
 	if (needpass)
 	{
-		udbs=userdbshadow(USERDB "shadow.dat", userid);
+		udbs=userdbshadow(USERDB "shadow.db", userid);
 
 		if (udbs)
 		{
@@ -129,7 +129,7 @@
 {
 	struct userdbs *u;
 
-	userdb_init(USERDB ".dat");
+	userdb_init(USERDB ".db");
 
 	for (u=userdb_enum_first(); u; u=userdb_enum_next())
 	{
diff -ruN courier-authlib-0.59.1.orig/README.authdebug.html.in courier-authlib-0.59.1/README.authdebug.html.in
--- courier-authlib-0.59.1.orig/README.authdebug.html.in	2004-11-26 01:07:02 +1000
+++ courier-authlib-0.59.1/README.authdebug.html.in	2007-01-28 00:49:47 +1000
@@ -147,7 +147,7 @@
 Apr 14 14:07:15 billdog authdaemond: cram: only supports authtype=cram-*
 Apr 14 14:07:15 billdog authdaemond: authcram: REJECT - try next module
 Apr 14 14:07:15 billdog authdaemond: authuserdb: trying this module
-Apr 14 14:07:15 billdog authdaemond: userdb: opened /etc/userdb.dat
+Apr 14 14:07:15 billdog authdaemond: userdb: opened /etc/courier-imap/userdb.db
 Apr 14 14:07:15 billdog authdaemond: userdb: looking up 'brian'
 Apr 14 14:07:15 billdog authdaemond: userdb: entry not found
 Apr 14 14:07:15 billdog authdaemond: authuserdb: REJECT - try next module
@@ -165,8 +165,8 @@
   <li>It tried 'authcram', but since this was a request with authtype=login
     (rather than authtype=cram-md5, say), this module cannot handle it so it
     REJECTs</li>
-  <li>'authuserdb' has a go. In this case there is an /etc/userdb.dat file
-    for it to look in, but the requested username 'brian' does not exist in
+  <li>'authuserdb' has a go. In this case there is an /etc/courier-imap/userdb.db
+    file for it to look in, but the requested username 'brian' does not exist in
     there, so it REJECTs</li>
   <li>'authpam' has a go. It finds the username and home directory in
     /etc/passwd, and then calls the PAM subsystem to authenticate. The
diff -ruN courier-authlib-0.59.1.orig/README_authlib.html.in courier-authlib-0.59.1/README_authlib.html.in
--- courier-authlib-0.59.1.orig/README_authlib.html.in	2006-12-31 03:11:36 +1000
+++ courier-authlib-0.59.1/README_authlib.html.in	2007-01-28 00:49:47 +1000
@@ -1246,11 +1246,11 @@
 ><P
 >This command creates the actual database, <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > and
 <TT
 CLASS="FILENAME"
->@userdb@shadow.dat</TT
+>@userdb@shadow.db</TT
 > from the plain text file
 <TT
 CLASS="FILENAME"
@@ -1261,11 +1261,11 @@
 ><P
 >Courier reads <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > and
 <TT
 CLASS="FILENAME"
->@userdb@shadow.dat</TT
+>@userdb@shadow.db</TT
 > only. The plain text source,
 <TT
 CLASS="FILENAME"
diff -ruN courier-authlib-0.59.1.orig/userdb/makeuserdb.8.in courier-authlib-0.59.1/userdb/makeuserdb.8.in
--- courier-authlib-0.59.1.orig/userdb/makeuserdb.8.in	2006-03-25 23:31:53 +1000
+++ courier-authlib-0.59.1/userdb/makeuserdb.8.in	2007-01-28 00:49:47 +1000
@@ -22,24 +22,24 @@
 
 .SH "DESCRIPTION"
 .PP
-\fBmakeuserdb\fR creates \fI@userdb@.dat\fR from
+\fBmakeuserdb\fR creates \fI@userdb@.db\fR from
 the contents of \fI@userdb@\fR\&.
 \fI@userdb@\fR\&'s contents are described later in this document.
 \fBMaildrop\fR,
 \fBCourier\fR, and other applications use
-\fI@userdb@.dat\fR as a
+\fI@userdb@.db\fR as a
 substitute/complement for your system password file.
 The usual purpose for
-\fI@userdb@.dat\fR is to specify "virtual" accounts - accounts
+\fI@userdb@.db\fR is to specify "virtual" accounts - accounts
 that do
 not have an associated system login.
 Usually (but not necessarily) all virtual accounts share the same
 system userid.
-\fI@userdb@.dat\fR may also replace
+\fI@userdb@.db\fR may also replace
 your system password file. Because the system password file is a text file,
 when there's a large number of accounts it will be significantly faster to
 search
-\fI@userdb.dat@\fR, which is a binary database,
+\fI@userdb@.db\fR, which is a binary database,
 instead of a flat text file that the system password file usually is.
 .PP
 The \fBmakeuserdb\fR command can be safely executed during
@@ -82,7 +82,7 @@
 Fields may be
 specified in any order. Here are all the currently defined fields.  Note that
 not every field is used by every application that reads
-\fI@userdb@.dat\fR\&.
+\fI@userdb@.db\fR\&.
 .sp
 .RS
 .PP
@@ -135,12 +135,12 @@
 \fBmaildirquota\fR(7)
 for additional information.
 .RE
-.SS "@USERDB@SHADOW.DAT"
+.SS "@USERDB@SHADOW.DB"
 .PP
 All fields whose name ends with 'pw' will NOT copied to
-\fI@userdb@.dat\fR\&. These fields will be copied to
-\fI@userdb@shadow.dat\fR\&.
-\fBmakeuserdb\fR creates \fI@userdb@shadow.dat\fR
+\fI@userdb@.db\fR\&. These fields will be copied to
+\fI@userdb@shadow.db\fR\&.
+\fBmakeuserdb\fR creates \fI@userdb@shadow.db\fR
 without any group and world permissions.
 Note that \fBmakeuserdb\fR reports an error
 if \fB@userdb@\fR has any group
@@ -166,7 +166,7 @@
 .PP
 After saving the output of \fBpw2userdb\fR, you must still run
 \fBmakeuserdb\fR to create
-\fI@userdb@.dat\fR\&.
+\fI@userdb@.db\fR\&.
 .PP
 \fBvchkpw2userdb\fR converts a vpopmail-style
 directory hierarchy to the \fI@userdb@\fR format.
@@ -210,7 +210,7 @@
 .RE
 .PP
 It is still necessary to run \fBmakeuserdb\fR, of course, to
-create the binary database file \fI@userdb@.dat\fR
+create the binary database file \fI@userdb@.db\fR
 .PP
 NOTE:  You are still required to create the \fB@userdb@\fR entry
 which maps
@@ -245,8 +245,8 @@
 
 .nf
 \fI@userdb@\fR
-\fI@userdb@.dat\fR
-\fI@userdb@shadow.dat\fR
+\fI@userdb@.db\fR
+\fI@userdb@shadow.db\fR
 \fI@tmpdir@/userdb.tmp\fR - temporary file
 \fI@tmpdir@/userdbshadow.tmp\fR - temporary file
 .fi
diff -ruN courier-authlib-0.59.1.orig/userdb/makeuserdb.html.in courier-authlib-0.59.1/userdb/makeuserdb.html.in
--- courier-authlib-0.59.1.orig/userdb/makeuserdb.html.in	2006-03-25 23:31:54 +1000
+++ courier-authlib-0.59.1/userdb/makeuserdb.html.in	2007-01-28 00:49:47 +1000
@@ -83,7 +83,7 @@
 >makeuserdb</B
 > creates <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > from
 the contents of <TT
 CLASS="FILENAME"
@@ -103,13 +103,13 @@
 >, and other applications use
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > as a
 substitute/complement for your system password file.
 The usual purpose for
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > is to specify "virtual" accounts - accounts
 that do
 not have an associated system login.
@@ -117,14 +117,14 @@
 system userid.
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > may also replace
 your system password file. Because the system password file is a text file,
 when there's a large number of accounts it will be significantly faster to
 search
 <TT
 CLASS="FILENAME"
->@userdb.dat@</TT
+>@userdb@.db</TT
 >, which is a binary database,
 instead of a flat text file that the system password file usually is.</P
 ><P
@@ -285,7 +285,7 @@
 not every field is used by every application that reads
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 >.</P
 ><A
 NAME="AEN73"
@@ -476,24 +476,24 @@
 ><H3
 ><TT
 CLASS="FILENAME"
->@userdb@shadow.dat</TT
+>@userdb@shadow.db</TT
 ></H3
 ><P
 >All fields whose name ends with 'pw' will NOT copied to
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 >. These fields will be copied to
 <TT
 CLASS="FILENAME"
->@userdb@shadow.dat</TT
+>@userdb@shadow.db</TT
 >.
 <B
 CLASS="COMMAND"
 >makeuserdb</B
 > creates <TT
 CLASS="FILENAME"
->@userdb@shadow.dat</TT
+>@userdb@shadow.db</TT
 >
 without any group and world permissions.
 Note that <B
@@ -578,7 +578,7 @@
 > to create
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 >.</P
 ><P
 ><B
@@ -702,7 +702,7 @@
 >, of course, to
 create the binary database file <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 ></P
 ><P
 >NOTE:  You are still required to create the <B
@@ -806,11 +806,11 @@
 ><br>
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 ><br>
 <TT
 CLASS="FILENAME"
->@userdb@shadow.dat</TT
+>@userdb@shadow.db</TT
 ><br>
 <TT
 CLASS="FILENAME"
diff -ruN courier-authlib-0.59.1.orig/userdb/makeuserdb.in courier-authlib-0.59.1/userdb/makeuserdb.in
--- courier-authlib-0.59.1.orig/userdb/makeuserdb.in	2006-03-25 23:31:21 +1000
+++ courier-authlib-0.59.1/userdb/makeuserdb.in	2007-01-28 00:52:08 +1000
@@ -27,10 +27,10 @@
 	$dbfile=~s/\/$//;
 }
 
-$datfile=$dbfile.".dat";
+$datfile=$dbfile.".db";
 # XXX the lock file here is etc/userdb.lock but the userdb command uses etc/.lock.userdb
 $lockfile=$dbfile.".lock";
-$shadowfile=$dbfile."shadow.dat";
+$shadowfile=$dbfile."shadow.db";
 $tmpdatfile=$dbfile.".tmp";
 $tmpshadowfile=$dbfile."shadow.tmp";
 
diff -ruN courier-authlib-0.59.1.orig/userdb/userdb.8.in courier-authlib-0.59.1/userdb/userdb.8.in
--- courier-authlib-0.59.1.orig/userdb/userdb.8.in	2004-10-21 11:31:20 +1100
+++ courier-authlib-0.59.1/userdb/userdb.8.in	2007-01-28 00:49:47 +1000
@@ -141,14 +141,14 @@
 \fBuserdb\fR produces a list, on standard output, of
 all the fields in \fI@userdb@\fR for this
 \fIaddr\fR\&.
-.SS "REBUILDING @USERDB@.DAT"
+.SS "REBUILDING @USERDB@.DB"
 .PP
 The actual virtual account/address database is
-\fI@userdb@.dat\fR\&.
+\fI@userdb@.db\fR\&.
 This is a binary database file. \fB@userdb@\fR is the plain text
 version. After running \fBuserdb\fR, execute the
 \fBmakeuserdb\fR(8) command to rebuild
-\fI@userdb@.dat\fR for the changes to take effect.
+\fI@userdb@.db\fR for the changes to take effect.
 .SH "BUGS"
 .PP
 \fIaddr\fR must be unique.
diff -ruN courier-authlib-0.59.1.orig/userdb/userdb.c courier-authlib-0.59.1/userdb/userdb.c
--- courier-authlib-0.59.1.orig/userdb/userdb.c	2006-10-29 05:22:52 +1000
+++ courier-authlib-0.59.1/userdb/userdb.c	2007-01-28 00:49:47 +1000
@@ -27,7 +27,7 @@
 static int initialized=0;
 int userdb_debug_level=0;
 
-/* Open userdb.dat, if already opened, see if it changed, if so reopen */
+/* Open userdb.db, if already opened, see if it changed, if so reopen */
 
 void userdb_init(const char *n)
 {
@@ -90,7 +90,7 @@
 	userdb_debug_level = lvl;
 }
 
-/* Fetch a record from userdb.dat */
+/* Fetch a record from userdb.db */
 
 char	*userdb(const char *u)
 {
@@ -302,7 +302,7 @@
 	return NULL;
 }
 
-/* Extracted a userdb.dat record, convert it to a userdbs structure */
+/* Extracted a userdb.db record, convert it to a userdbs structure */
 
 struct userdbs *userdb_creates(const char *u)
 {
diff -ruN courier-authlib-0.59.1.orig/userdb/userdb.h courier-authlib-0.59.1/userdb/userdb.h
--- courier-authlib-0.59.1.orig/userdb/userdb.h	2004-04-19 02:54:39 +1100
+++ courier-authlib-0.59.1/userdb/userdb.h	2007-01-28 00:49:47 +1000
@@ -15,7 +15,7 @@
 #endif
 
 /*
-	Functions to access local/config/userdb.dat
+	Functions to access local/config/userdb.db
 */
 
 void userdb_set_debug(int);
diff -ruN courier-authlib-0.59.1.orig/userdb/userdb.html.in courier-authlib-0.59.1/userdb/userdb.html.in
--- courier-authlib-0.59.1.orig/userdb/userdb.html.in	2004-10-21 11:31:22 +1100
+++ courier-authlib-0.59.1/userdb/userdb.html.in	2007-01-28 00:49:47 +1000
@@ -518,13 +518,13 @@
 ><H3
 >REBUILDING <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 ></H3
 ><P
 >The actual virtual account/address database is
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 >.
 This is a binary database file. <B
 CLASS="COMMAND"
@@ -547,7 +547,7 @@
 > command to rebuild
 <TT
 CLASS="FILENAME"
->@userdb@.dat</TT
+>@userdb@.db</TT
 > for the changes to take effect.</P
 ></DIV
 ></DIV
diff -ruN courier-authlib-0.59.1.orig/userdb/userdbpw.8.in courier-authlib-0.59.1/userdb/userdbpw.8.in
--- courier-authlib-0.59.1.orig/userdb/userdbpw.8.in	2004-10-21 11:31:21 +1100
+++ courier-authlib-0.59.1/userdb/userdbpw.8.in	2007-01-28 00:49:47 +1000
@@ -49,11 +49,11 @@
 authenticate.  Therefore, applications that use challenge/response
 authentication will store intermediate HMAC contexts in the "pw" fields in the
 userdb database, which will be compiled into the
-\fIuserdbshadow.dat\fR
+\fIuserdbshadow.db\fR
 database, which has group and world permissions turned off. The
 userdb library also requires that the cleartext userdb source for the
-\fIuserdb.dat\fR and
-\fIuserdbshadow.dat\fR databases is also stored with the
+\fIuserdb.db\fR and
+\fIuserdbshadow.db\fR databases is also stored with the
 group and world permissions turned off.
 .PP
 \fBuserdbpw\fR is usually used together in a pipe with
diff -ruN courier-authlib-0.59.1.orig/userdb/userdbpw.html.in courier-authlib-0.59.1/userdb/userdbpw.html.in
--- courier-authlib-0.59.1.orig/userdb/userdbpw.html.in	2004-10-21 11:31:22 +1100
+++ courier-authlib-0.59.1/userdb/userdbpw.html.in	2007-01-28 00:49:47 +1000
@@ -130,17 +130,17 @@
 userdb database, which will be compiled into the
 <TT
 CLASS="FILENAME"
->userdbshadow.dat</TT
+>userdbshadow.db</TT
 >
 database, which has group and world permissions turned off. The
 userdb library also requires that the cleartext userdb source for the
 <TT
 CLASS="FILENAME"
->userdb.dat</TT
+>userdb.db</TT
 > and
 <TT
 CLASS="FILENAME"
->userdbshadow.dat</TT
+>userdbshadow.db</TT
 > databases is also stored with the
 group and world permissions turned off.</P
 ><P