I took a look at the requriements listed on the web site, and there is nothing out of the ordinary.  I have high enough versions for php and mysql as before.
the front page of mantis wouldn't even display.  I received a memory exceeded error in the php error log.  I raised that to 10M and then ran it again.  Now the login page works. 
So as usual i tried to access the admin page to check everything and convert my database - and I get the following error:
[23-Feb-2010 10:56:22] PHP Fatal error:  Trying to clone an uncloneable object o
f class ReflectionClass in /usr/local/apache2/htdocs/mantisbt-1.2.0/core/utility
_api.php on line 195
I never had to really change anything to upgrade mantis before.  So I just wanted to be sure I was not missing some release notes somewhere - or upgrade procedures.
--- On Mon, 2/22/10, John Reese <jreese@leetcode.net> wrote:

From: John Reese <jreese@leetcode.net>
Subject: [mantisbt-help] MantisBT 1.2.0 Released
To: mantisbt-announce@lists.sourceforge.net, mantisbt-dev@lists.sourceforge.net, mantisbt-help@lists.sourceforge.net
Date: Monday, February 22, 2010, 3:52 PM

MantisBT Release Notes

1.2.0 Stable Release

This release marks the first official release in the 1.2.x series of MantisBT.
1.2.0 is a major feature release for MantisBT, and includes many bugfixes and
enhancements over the 1.1.x stable branch.  All users of 1.1.x are highly
encouraged to upgrade as soon as possible.

A full changelog for the 1.2.x series can be found on the official site. [1]

There are many new features added to 1.2.0, including:

  - Converted the MantisBT Manual to Docbook format, and added a new Developer's
    Guide manual, both of which are compiled and included in every release

  - Implemented a plugin system with many plugins already released [2]

  - Global categories available to all projects, as well as project categories
    inheriting from parent projects to child projects;  both are optional

  - Tracked change history for textarea fields (Description, etc) and bug notes

  - Customizable sets of columns for View Issues page and export formats

  - Combined simple and advanced views into a single, configurable view that
    allows selecting exactly what fields to show or hide

  - Improved roadmap and changelog pages, including version release dates, and
    permalinks to individual versions

  - Marking versions as obsolete to hide them from the roadmap and changelog

  - More configuration options for rebranding MantisBT installations

  - Improved support for PostgreSQL databases

  - Improved support for UTF-8 localizations and content

  - Implemented custom search providers for Firefox and Internet Explorer

  - Implemented localized timestamps using according to user-preferred timezones

There have also been many improvements to the codebase beyond adding features:

  - Migrated to parameterised database queries throughout the codebase for both
    performance and security improvements

  - Added PHPDoc compatible documentation to all internal API's

  - Removed many hardcoded references to access levels and other enumerations,
    for improved customizability.

  - Migrated away from DATETIME fields to integer timestamps for timezone usage

  - All 3rd party code is now contained within the library/ path, including
    documentation on library versions and any patches applied

  - Initial support for MySQL 6 and PHP 5.3

[1] The changelog is split between multiple releases:

     1.2.0a1    http://www.mantisbt.org/bugs/changelog_page.php?version_id=89
     1.2.0a2    http://www.mantisbt.org/bugs/changelog_page.php?version_id=96
     1.2.0a3    http://www.mantisbt.org/bugs/changelog_page.php?version_id=104
     1.2.0rc1   http://www.mantisbt.org/bugs/changelog_page.php?version_id=98
     1.2.0rc2   http://www.mantisbt.org/bugs/changelog_page.php?version_id=106
     1.2.0      http://www.mantisbt.org/bugs/changelog_page.php?version_id=108

[2] MantisForge is now the preferred code collaboration site for MantisBT,
     including free hosting of MantisBT-related Git repositories for development
     of contributions to MantisBT itself or community plugins.


John Reese

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