diff -Naur cyrus-imapd-2.5.ori/imap/imapd.c cyrus-imapd-2.5/imap/imapd.c
--- cyrus-imapd-2.5.ori/imap/imapd.c    2013-07-31 13:09:24.089114102 +0200
+++ cyrus-imapd-2.5/imap/imapd.c        2013-07-31 13:16:34.880113725 +0200
@@ -320,6 +320,7 @@
     { "MOVE",                  2 }, /* draft */
     { "SPECIAL-USE",           2 },
     { "CREATE-SPECIAL-USE",    2 },
+    { "DIGEST=SHA1",           2 },

 #ifdef HAVE_SSL
     { "URLAUTH",               2 },
@@ -4376,6 +4377,13 @@
            }
            else goto badatt;
            break;
+
+       case 'D':
+           if (!strcmp(fetchatt.s, "DIGEST.SHA1")) {
+               fetchitems |= FETCH_GUID;
+           }
+           else goto badatt;
+           break;

        case 'E':
            if (!strcmp(fetchatt.s, "ENVELOPE")) {
@@ -4414,6 +4422,12 @@
            if (!strcmp(fetchatt.s, "RFC822")) {
                fa->fetchitems |= FETCH_RFC822|FETCH_SETSEEN;
            }
+           else if (!strcmp(fetchatt.s, "RFC822.SHA1")) {
+               fetchitems |= FETCH_SHA1;
+           }
+           else if (!strcmp(fetchatt.s, "RFC822.FILESIZE")) {
+               fetchitems |= FETCH_FILESIZE;
+           }
            else if (!strcmp(fetchatt.s, "RFC822.HEADER")) {
                fa->fetchitems |= FETCH_HEADER;
            }
diff -Naur cyrus-imapd-2.5.ori/imap/imapd.h cyrus-imapd-2.5/imap/imapd.h
--- cyrus-imapd-2.5.ori/imap/imapd.h    2013-07-31 13:09:24.087113533 +0200
+++ cyrus-imapd-2.5/imap/imapd.h        2013-07-31 13:17:44.405190499 +0200
@@ -124,7 +124,10 @@
 /*     FETCH_UNCACHEDHEADER =      (1<<11) -- obsolete */
     FETCH_IS_PARTIAL =          (1<<12), /* this is the PARTIAL command */
     FETCH_MODSEQ =             (1<<13),
-    FETCH_ANNOTATION =         (1<<14)
+    FETCH_ANNOTATION =         (1<<14),
+    FETCH_GUID   =              (1<<15),
+    FETCH_SHA1   =              (1<<16),
+    FETCH_FILESIZE =            (1<<17)
 };

 enum {
diff -Naur cyrus-imapd-2.5.ori/imap/index.c cyrus-imapd-2.5/imap/index.c
--- cyrus-imapd-2.5.ori/imap/index.c    2013-07-31 13:09:24.085114556 +0200
+++ cyrus-imapd-2.5/imap/index.c        2013-07-31 13:21:23.728242893 +0200
@@ -2950,7 +2950,7 @@
     }

     /* Open the message file if we're going to need it */
-    if ((fetchitems & (FETCH_HEADER|FETCH_TEXT|FETCH_RFC822)) ||
+    if ((fetchitems & (FETCH_HEADER|FETCH_TEXT|FETCH_SHA1|FETCH_RFC822)) ||
        fetchargs->cache_atleast > record.cache_version ||
        fetchargs->binsections || fetchargs->sizesections ||
        fetchargs->bodysections) {
@@ -2976,6 +2976,11 @@
     if (fetchitems & FETCH_UID) {
        prot_printf(state->out, "%cUID %u", sepchar, record.uid);
        sepchar = ' ';
+       if (fetchitems & FETCH_GUID) {
+            prot_printf(state->out, "%cDIGEST.SHA1 %s", sepchar,
+            message_guid_encode(&im->record.guid));
+            sepchar = ' ';
+       }
     }
     if (fetchitems & FETCH_INTERNALDATE) {
        time_t msgdate = record.internaldate;
@@ -2996,6 +3001,25 @@
        prot_printf(state->out, "%cRFC822.SIZE %u",
                    sepchar, record.size);
        sepchar = ' ';
+       if (fetchitems & FETCH_FILESIZE) {
+          if (!msg_base) {
+              char *fname = mailbox_message_fname(mailbox, im->record.uid);
+              struct stat sbuf;
+              /* Find the size of the message file */
+              if (stat(fname, &sbuf) == -1)
+                   syslog(LOG_ERR, "IOERROR: stat on %s: %m", fname);
+              else
+                    msg_size = sbuf.st_size;
+          }
+          prot_printf(state->out, "%cRFC822.FILESIZE %lu", sepchar, (long unsigned)msg_size);
+          sepchar = ' ';
+       }
+       if (fetchitems & FETCH_SHA1) {
+          struct message_guid tmpguid;
+          message_guid_generate(&tmpguid, msg_base, msg_size);
+          prot_printf(state->out, "%cRFC822.SHA1 %s", sepchar, message_guid_encode(&tmpguid));
+          sepchar = ' ';
+       }
     }
     if ((fetchitems & FETCH_ANNOTATION)) {
        prot_printf(state->out, "%cANNOTATION (", sepchar);