diff --git a/plugins/sudoers/auth/bsdauth.c b/plugins/sudoers/auth/bsdauth.c
index e0292d634..821286dcf 100644
--- a/plugins/sudoers/auth/bsdauth.c
+++ b/plugins/sudoers/auth/bsdauth.c
@@ -60,6 +60,10 @@ bsdauth_init(struct passwd *pw, sudo_auth *auth)
     static struct bsdauth_state state;
     debug_decl(bsdauth_init, SUDOERS_DEBUG_AUTH);
 
+    /* Only initialize once. */
+    if (auth->data != NULL)
+	debug_return_int(AUTH_SUCCESS);
+
     /* Get login class based on auth user, which may not be invoking user. */
     if (pw->pw_class && *pw->pw_class)
 	state.lc = login_getclass(pw->pw_class);
diff --git a/plugins/sudoers/auth/fwtk.c b/plugins/sudoers/auth/fwtk.c
index 7f3385d0f..3afe4b225 100644
--- a/plugins/sudoers/auth/fwtk.c
+++ b/plugins/sudoers/auth/fwtk.c
@@ -50,6 +50,10 @@ sudo_fwtk_init(struct passwd *pw, sudo_auth *auth)
     char resp[128];			/* Response from the server */
     debug_decl(sudo_fwtk_init, SUDOERS_DEBUG_AUTH);
 
+    /* Only initialize once. */
+    if (auth->data != NULL)
+	debug_return_int(AUTH_SUCCESS);
+
     if ((confp = cfg_read("sudo")) == (Cfg *)-1) {
 	sudo_warnx("%s", U_("unable to read fwtk config"));
 	debug_return_int(AUTH_FATAL);
@@ -69,6 +73,7 @@ sudo_fwtk_init(struct passwd *pw, sudo_auth *auth)
 	sudo_warnx(U_("authentication server error:\n%s"), resp);
 	debug_return_int(AUTH_FATAL);
     }
+    auth->data = (void *) confp;
 
     debug_return_int(AUTH_SUCCESS);
 }
diff --git a/plugins/sudoers/auth/kerb5.c b/plugins/sudoers/auth/kerb5.c
index a6072269f..6bb00a804 100644
--- a/plugins/sudoers/auth/kerb5.c
+++ b/plugins/sudoers/auth/kerb5.c
@@ -135,7 +135,9 @@ sudo_krb5_init(struct passwd *pw, sudo_auth *auth)
     char		cache_name[64], *pname = pw->pw_name;
     debug_decl(sudo_krb5_init, SUDOERS_DEBUG_AUTH);
 
-    auth->data = (void *) &sudo_krb5_data; /* Stash all our data here */
+    /* Only initialize once. */
+    if (auth->data != NULL)
+	debug_return_int(AUTH_SUCCESS);
 
     if (sudo_krb5_instance != NULL) {
 	int len = asprintf(&pname, "%s%s%s", pw->pw_name,
@@ -171,6 +173,8 @@ sudo_krb5_init(struct passwd *pw, sudo_auth *auth)
 	goto done;
     }
 
+    auth->data = (void *) &sudo_krb5_data; /* Stash all our data here */
+
 done:
     if (sudo_krb5_instance != NULL)
 	free(pname);
diff --git a/plugins/sudoers/auth/passwd.c b/plugins/sudoers/auth/passwd.c
index 566881f68..b2046eca2 100644
--- a/plugins/sudoers/auth/passwd.c
+++ b/plugins/sudoers/auth/passwd.c
@@ -45,6 +45,10 @@ sudo_passwd_init(struct passwd *pw, sudo_auth *auth)
 {
     debug_decl(sudo_passwd_init, SUDOERS_DEBUG_AUTH);
 
+    /* Only initialize once. */
+    if (auth->data != NULL)
+	debug_return_int(AUTH_SUCCESS);
+
 #ifdef HAVE_SKEYACCESS
     if (skeyaccess(pw, user_tty, NULL, NULL) == 0)
 	debug_return_int(AUTH_FAILURE);
diff --git a/plugins/sudoers/auth/secureware.c b/plugins/sudoers/auth/secureware.c
index dd7aa42eb..6980b75dc 100644
--- a/plugins/sudoers/auth/secureware.c
+++ b/plugins/sudoers/auth/secureware.c
@@ -55,6 +55,10 @@ sudo_secureware_init(struct passwd *pw, sudo_auth *auth)
 {
     debug_decl(sudo_secureware_init, SUDOERS_DEBUG_AUTH);
 
+    /* Only initialize once. */
+    if (auth->data != NULL)
+	debug_return_int(AUTH_SUCCESS);
+
 #ifdef __alpha
     if (crypt_type == INT_MAX)
 	debug_return_int(AUTH_FAILURE);			/* no shadow */
diff --git a/plugins/sudoers/auth/securid5.c b/plugins/sudoers/auth/securid5.c
index 698953fc2..628ba1cfa 100644
--- a/plugins/sudoers/auth/securid5.c
+++ b/plugins/sudoers/auth/securid5.c
@@ -63,14 +63,19 @@ sudo_securid_init(struct passwd *pw, sudo_auth *auth)
     static SDI_HANDLE sd_dat;			/* SecurID handle */
     debug_decl(sudo_securid_init, SUDOERS_DEBUG_AUTH);
 
-    auth->data = (void *) &sd_dat;		/* For method-specific data */
-
-    /* Start communications */
-    if (AceInitialize() != SD_FALSE)
+    /* Only initialize once. */
+    if (auth->data != NULL)
 	debug_return_int(AUTH_SUCCESS);
 
-    sudo_warnx("%s", U_("failed to initialise the ACE API library"));
-    debug_return_int(AUTH_FATAL);
+    /* Start communications */
+    if (AceInitialize() == SD_FALSE) {
+	sudo_warnx("%s", U_("failed to initialise the ACE API library"));
+	debug_return_int(AUTH_FATAL);
+    }
+
+    auth->data = (void *) &sd_dat;		/* For method-specific data */
+
+    debug_return_int(AUTH_SUCCESS);
 }
 
 /*