Redmine

We have upgraded our Redmine from 0.8 to 1.3 version.

Now we got problem with old diffs in wiki history:
Processing WikiController#diff (for xxx.xxx.xxx.xxx at 2012-02-08 11:05:59) [GET]                                                             
  Parameters: {"commit"=>"View differences", "project_id"=>"xxxxxxxx", "action"=>"diff", "id"=>"Wiki", "version"=>"7", "controller"=>"wiki
", "version_from"=>"6"}                                                                                                                     

Zlib::DataError (incorrect header check):                                                                                                   
  app/models/wiki_content.rb:96:in `inflate'                                                                                                
  app/models/wiki_content.rb:96:in `text'                                                                                                   
  app/models/wiki_page.rb:181:in `initialize'                                                                                               
  app/models/wiki_page.rb:114:in `new'                                                                                                      
  app/models/wiki_page.rb:114:in `diff'                                                                                                     
  app/controllers/wiki_controller.rb:195:in `diff'                                                                                          
  unicorn (4.1.1) lib/unicorn/http_server.rb:528:in `process_client'                                                                        
  unicorn (4.1.1) lib/unicorn/http_server.rb:600:in `worker_loop'                                                                           
  unicorn (4.1.1) lib/unicorn/http_server.rb:485:in `spawn_missing_workers'                                                                 
  unicorn (4.1.1) lib/unicorn/http_server.rb:135:in `start'                                                                                 
  unicorn (4.1.1) bin/unicorn_rails:209                                                                                                     
  /home/platform/.rvm/gems/ruby-1.8.7-p352@redmine/bin/unicorn_rails:19:in `load'                                                           
  /home/platform/.rvm/gems/ruby-1.8.7-p352@redmine/bin/unicorn_rails:19                                                                     

Rendering /export/redmine/redmine13/public/500.html (500 Internal Server Error)

Wiki content versions stored as gzip compressed blobs.
I found that decompression behavior was changed for Ruby 1.9: https://github.com/edavis10/redmine/commit/1dab1cd5cc9d46724b8d722d994737806ee22bb9#app/models/wiki_content.rb
This code also appeared in 1.3 and 1.3.1

But 1.9 supported with trunk only and it not works with stable versions running on Ruby 1.8.x
Should be other solution here :(

Redmine: 1.3
Ruby: 1.8.7
Rails: 2.3.14
MySQL: 5.0.77