diff -Naur cyrus-imapd-2.3.8.orig/configure.in cyrus-imapd-2.3.8/configure.in

--- cyrus-imapd-2.3.8.orig/configure.in	Thu Nov 30 18:11:16 2006

+++ cyrus-imapd-2.3.8/configure.in	Tue Jun 12 15:40:12 2007

@@ -119,7 +119,7 @@

 AC_CHECK_HEADERS(unistd.h sys/select.h sys/param.h stdarg.h)

 AC_REPLACE_FUNCS(memmove strcasecmp ftruncate strerror)

-AC_CHECK_FUNCS(strlcat strlcpy)

+AC_CHECK_FUNCS(strlcat strlcpy getgrouplist)

 AC_HEADER_DIRENT

 dnl do this before Berkeley DB/IPv6 detection

diff -Naur cyrus-imapd-2.3.8.orig/lib/auth_unix.c cyrus-imapd-2.3.8/lib/auth_unix.c

--- cyrus-imapd-2.3.8.orig/lib/auth_unix.c	Thu Nov 30 18:11:22 2006

+++ cyrus-imapd-2.3.8/lib/auth_unix.c	Tue Jun 12 15:42:22 2007

@@ -224,6 +224,12 @@

     struct passwd *pwd;

     struct group *grp;

     char **mem;

+#ifdef HAVE_GETGROUPLIST

+    gid_t gid;

+    int ret, ngroups;

+    gid_t *groupids = 0;

+    int i;

+#endif

     identifier = mycanonifyid(identifier, 0);

     if (!identifier) return 0;

@@ -239,7 +245,45 @@

 	return newstate;

     pwd = getpwnam(identifier);

-	

+#ifdef HAVE_GETGROUPLIST

+    gid = pwd ? pwd->pw_gid : (gid_t) -1;

+

+    // get number of groups user is member of into newstate->ngroups

+    getgrouplist(identifier, gid, NULL, &(newstate->ngroups));

+    // get the actual group ids.

+    do {

+	if (groupids)

+	    free(groupids);

+	groupids = (gid_t *)xmalloc(newstate->ngroups * sizeof(gid_t));

+

+	ngroups = newstate->ngroups;

+	ret = getgrouplist(identifier, gid, groupids, &(newstate->ngroups));

+	/*

+	 * This is tricky. We do this as long as getgrouplist tells us to

+	 * realloc _and_ the number of groups changes. It tells us to realloc

+	 * also in the case of failure...

+	 */

+    } while (ret != -1 && ngroups != newstate->ngroups);

+

+    if (ret == -1) {

+	newstate->ngroups = 0;

+	newstate->group = NULL;

+	goto err;

+    }

+

+    newstate->group = (char **)xmalloc(newstate->ngroups * sizeof(char *));

+    for (i = 0; i < newstate->ngroups; ++i ) {

+	struct group *group;

+

+	if (pwd || groupids[i] != gid) {

+	    if ((group = getgrgid(groupids[i])))

+		newstate->group[i] = xstrdup(group->gr_name);

+	}

+    }

+

+err:

+    free( groupids );

+#else

     setgrent();

     while ((grp = getgrent())) {

 	for (mem = grp->gr_mem; *mem; mem++) {

@@ -254,6 +298,8 @@

 	}

     }

     endgrent();

+#endif

+

     return newstate;

 }