[evolution] Fix a typo in a commit for a bug #666490

[Milan Crha <mcrha src gnome org>]

commit a1112c6e401a022f6222efffa5c149290d874663
Author: Milan Crha <mcrha redhat com>
Date:   Thu Dec 22 18:11:02 2011 +0100

    Fix a typo in a commit for a bug #666490

 mail/e-mail-session.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/mail/e-mail-session.c b/mail/e-mail-session.c
index 9ac0cad..b1dea64 100644
--- a/mail/e-mail-session.c
+++ b/mail/e-mail-session.c
@@ -268,9 +268,14 @@ user_message_exec (struct _user_message_msg *m,
 		user_message_response (
 			user_message_dialog, response, m);
 	} else {
+		gpointer user_data = m;
+
+		if (g_slist_length (m->button_captions) <= 1)
+			user_data = NULL;
+
 		g_signal_connect (
 			user_message_dialog, "response",
-			G_CALLBACK (user_message_response), NULL);
+			G_CALLBACK (user_message_response), user_data);
 		gtk_widget_show (user_message_dialog);
 	}
 }