diff --git a/htdocs/core/class/html.formmail.class.php b/htdocs/core/class/html.formmail.class.php
index 94ab828ee39..1b5d743c350 100644
--- a/htdocs/core/class/html.formmail.class.php
+++ b/htdocs/core/class/html.formmail.class.php
@@ -399,7 +399,7 @@ class FormMail extends Form
 
 
 
-			$out.= '<table class="border" width="100%">'."\n";
+			$out.= '<table class="border" width="100%" style="border-top: 1px solid #BBB;">'."\n";
 
 			// Substitution array
 			if (! empty($this->withsubstit))		// Unset or set ->withsubstit=0 to disable this.
diff --git a/htdocs/core/lib/functions.lib.php b/htdocs/core/lib/functions.lib.php
index 715095f96ae..99aa4ccc84f 100644
--- a/htdocs/core/lib/functions.lib.php
+++ b/htdocs/core/lib/functions.lib.php
@@ -5627,7 +5627,7 @@ function getCommonSubstitutionArray($outputlangs, $onlykey=0, $exclude=null, $ob
 			'__USER_LASTNAME__' => (string) $user->lastname,
 			'__USER_FIRSTNAME__' => (string) $user->firstname,
 			'__USER_FULLNAME__' => (string) $user->getFullName($outputlangs),
-			'__USER_SUPERVISOR_ID__' => (string) $user->fk_user
+			'__USER_SUPERVISOR_ID__' => (string) ($user->fk_user ? $user->fk_user : '0')
 			)
 		);
 	}