=== modified file 'lisp/net/gnutls.el'
--- lisp/net/gnutls.el	2012-02-12 21:40:25 +0000
+++ lisp/net/gnutls.el	2012-02-13 16:20:13 +0000
@@ -51,6 +51,19 @@
   :type '(choice (const nil)
 		 string))
 
+(defcustom gnutls-trustfiles
+  '(
+    "/etc/ssl/certs/ca-certificates.crt" ; Debian, Ubuntu, Gentoo and Arch Linux
+    "/etc/pki/tls/certs/ca-bundle.crt"   ; Fedora and RHEL
+    "/etc/ssl/ca-bundle.pem"             ; Suse
+    )
+  "List of CA bundle location filenames or a function returning said list.
+The files may be in PEM or DER format, as per the GnuTLS documentation.
+The files may not exist, in which case they will be ignored."
+  :group 'gnutls
+  :type '(choice (function :tag "Function to produce list of bundle filenames")
+                 (repeat (file :tag "Bundle filename"))))
+
 ;;;###autoload
 (defcustom gnutls-min-prime-bits nil
   "The minimum number of bits to be used in Diffie-Hellman key exchange.
@@ -118,7 +131,7 @@
 PROCESS is a process returned by `open-network-stream'.
 HOSTNAME is the remote hostname.  It must be a valid string.
 PRIORITY-STRING is as per the GnuTLS docs, default is \"NORMAL\".
-TRUSTFILES is a list of CA bundles.
+TRUSTFILES is a list of CA bundles.  It defaults to `gnutls-trustfiles'.
 CRLFILES is a list of CRL files.
 KEYLIST is an alist of (client key file, client cert file) pairs.
 MIN-PRIME-BITS is the minimum acceptable size of Diffie-Hellman keys
@@ -156,10 +169,12 @@
 It must be omitted, a number, or nil; if omitted or nil it
 defaults to GNUTLS_VERIFY_ALLOW_X509_V1_CA_CRT."
   (let* ((type (or type 'gnutls-x509pki))
-         (default-trustfile "/etc/ssl/certs/ca-certificates.crt")
          (trustfiles (or trustfiles
-                         (when (file-exists-p default-trustfile)
-                           (list default-trustfile))))
+                         (delq nil
+                               (mapcar (lambda (f) (and f (file-exists-p f) f))
+                                       (if (functionp gnutls-trustfiles)
+                                           (funcall gnutls-trustfiles)
+                                         gnutls-trustfiles)))))
          (priority-string (or priority-string
                               (cond
                                ((eq type 'gnutls-anon)