Index: uuid.admin.inc
===================================================================
RCS file: /cvs/drupal/contributions/modules/uuid/uuid.admin.inc,v
retrieving revision 1.1.2.2
diff -u -r1.1.2.2 uuid.admin.inc
--- uuid.admin.inc	11 Jun 2009 18:07:13 -0000	1.1.2.2
+++ uuid.admin.inc	28 Aug 2009 16:36:39 -0000
@@ -57,12 +57,12 @@
  */
 function uuid_sync() {
   if (variable_get('uuid_automatic_for_users', FALSE)) {
-    db_query("INSERT INTO {uuid_users} SELECT u.uid, UUID() FROM {users} AS u WHERE NOT EXISTS (SELECT uid FROM {uuid_users} WHERE uid = u.uid)");
+    db_query("INSERT INTO {uuid_users} SELECT u.uid, '%s' FROM {users} AS u WHERE NOT EXISTS (SELECT uid FROM {uuid_users} WHERE uid = u.uid)", uuid_uuid());
   }
 
   foreach (variable_get('uuid_automatic_for_nodes', array()) as $type) {
-    db_query("INSERT INTO {uuid_node} SELECT n.nid, UUID() FROM {node} AS n WHERE n.type = '%s' AND NOT EXISTS (SELECT nid FROM {uuid_node} WHERE nid = n.nid)", $type);
-    db_query("INSERT INTO {uuid_node_revisions} SELECT nr.vid, UUID() FROM {node_revisions} AS nr INNER JOIN {node} n ON nr.nid = n.nid WHERE n.type = '%s' AND NOT EXISTS (SELECT vid FROM {uuid_node_revisions} WHERE vid = nr.vid)", $type);
+    db_query("INSERT INTO {uuid_node} SELECT n.nid, '%s' FROM {node} AS n WHERE n.type = '%s' AND NOT EXISTS (SELECT nid FROM {uuid_node} WHERE nid = n.nid)", uuid_uuid(), $type);
+    db_query("INSERT INTO {uuid_node_revisions} SELECT nr.vid, '%s' FROM {node_revisions} AS nr INNER JOIN {node} n ON nr.nid = n.nid WHERE n.type = '%s' AND NOT EXISTS (SELECT vid FROM {uuid_node_revisions} WHERE vid = nr.vid)", uuid_uuid(), $type);
   }
 
   drupal_set_message(t("UUID tables have been updated."));
Index: uuid.module
===================================================================
RCS file: /cvs/drupal/contributions/modules/uuid/uuid.module,v
retrieving revision 1.1.2.4
diff -u -r1.1.2.4 uuid.module
--- uuid.module	11 Jun 2009 18:07:13 -0000	1.1.2.4
+++ uuid.module	28 Aug 2009 16:38:55 -0000
@@ -43,12 +43,12 @@
           db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, '%s')", $node->vid, $node->revision_uuid);
         }
         else {
-          db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, UUID())", $node->vid);
+          db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, '%s')", $node->vid, uuid_uuid());
         }
       }
       else if (in_array($node->type, $automatic_types)) {
-        db_query('INSERT INTO {uuid_node} (nid, uuid) VALUES (%d, UUID())', $node->nid);
-        db_query('INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, UUID())', $node->vid);
+        db_query("INSERT INTO {uuid_node} (nid, uuid) VALUES (%d, '%s')", $node->nid, uuid_uuid());
+        db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, '%s')", $node->vid, uuid_uuid());
       }
       break;
     case 'update':
@@ -57,7 +57,7 @@
           db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, '%s')", $node->vid, $node->revision_uuid);
         }
         else {
-          db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, UUID())", $node->vid);
+          db_query("INSERT INTO {uuid_node_revisions} (vid, uuid) VALUES (%d, '%s')", $node->vid, uuid_uuid());
         }
       }
       break;
@@ -127,7 +127,7 @@
         db_query("INSERT INTO {uuid_users} (uid, uuid) VALUES (%d, '%s')", $user->uid, $user->uuid);
       }
       else if (variable_get('uuid_automatic_for_users', FALSE)) {
-        db_query('INSERT INTO {uuid_users} (uid, uuid) VALUES (%d, UUID())', $user->uid);
+        db_query("INSERT INTO {uuid_users} (uid, uuid) VALUES (%d, '%s')", $user->uid, uuid_uuid());
       }
       break;
     case 'update':
@@ -168,3 +168,61 @@
 function uuid_is_valid($uuid) {
   return (boolean) preg_match('/^[A-Fa-f0-9]{8}-[A-Fa-f0-9]{4}-[A-Fa-f0-9]{4}-[A-Fa-f0-9]{4}-[A-Fa-f0-9]{12}$/', $uuid);
 }
+
+/**
+ * @return a Universally Unique IDentifier
+ */
+function uuid_uuid() {
+  if ($GLOBALS['db_type'] != 'pgsql') {
+    return db_result(db_query("SELECT UUID();"));
+  }
+  
+  /**
+   * @desc  Generates a Universally Unique IDentifier, version 4.
+   * 
+   * RFC 4122 (http://www.ietf.org/rfc/rfc4122.txt) defines a special type of Globally
+   * Unique IDentifiers (GUID), as well as several methods for producing them. One
+   * such method, described in section 4.4, is based on truly random or pseudo-random
+   * number generators, and is therefore implementable in a language like PHP.
+   *
+   * We choose to produce pseudo-random numbers with the Mersenne Twister, and to always
+   * limit single generated numbers to 16 bits (ie. the decimal value 65535). That is
+   * because, even on 32-bit systems, PHP's RAND_MAX will often be the maximum *signed*
+   * value, with only the equivalent of 31 significant bits. Producing two 16-bit random
+   * numbers to make up a 32-bit one is less efficient, but guarantees that all 32 bits
+   * are random.
+   *
+   * The algorithm for version 4 UUIDs (ie. those based on random number generators)
+   * states that all 128 bits separated into the various fields (32 bits, 16 bits, 16 bits,
+   * 8 bits and 8 bits, 48 bits) should be random, except : (a) the version number should
+   * be the last 4 bits in the 3rd field, and (b) bits 6 and 7 of the 4th field should
+   * be 01. We try to conform to that definition as efficiently as possible, generating
+   * smaller values where possible, and minimizing the number of base conversions.
+   *
+   * @copyright   Copyright (c) CFD Labs, 2006. This function may be used freely for
+   *              any purpose ; it is distributed without any form of warranty whatsoever.
+   * @author      David Holmes <dholmes@cfdsoftware.net>
+   *
+   * @return  string  A UUID, made up of 32 hex digits and 4 hyphens.
+   * 
+   * @see  http://php.net/manual/en/function.uniqid.php#65879
+   */
+   
+  // If the function provided by the uuid pecl extension is available, use that.
+  if( function_exists("uuid_create")) {
+    return uuid_create(UUID_TYPE_DEFAULT);
+  }
+
+  // The field names refer to RFC 4122 section 4.1.2
+  return sprintf('%04x%04x-%04x-%03x4-%04x-%04x%04x%04x',
+    mt_rand(0, 65535), mt_rand(0, 65535), // 32 bits for "time_low"
+    mt_rand(0, 65535), // 16 bits for "time_mid"
+    mt_rand(0, 4095),  // 12 bits before the 0100 of (version) 4 for "time_hi_and_version"
+    bindec(substr_replace(sprintf('%016b', mt_rand(0, 65535)), '01', 6, 2)),
+      // 8 bits, the last two of which (positions 6 and 7) are 01, for "clk_seq_hi_res"
+      // (hence, the 2nd hex digit after the 3rd hyphen can only be 1, 5, 9 or d)
+      // 8 bits for "clk_seq_low"
+    mt_rand(0, 65535), mt_rand(0, 65535), mt_rand(0, 65535) // 48 bits for "node" 
+  );
+}
+