PHP 5.3 related issue in admin page

When I try go to admin page (/index.php/admin) I see this error:

 So here's the error:
Function split() is deprecated

File: modules/gallery/helpers/gallery_block.php, line: 75
And here's how we got there:

    *

      gallery_error_Core::error_handler( 8192, Function split() is deprecated, modules/gallery/helpers/gallery_block.php, 75, Array
      (
          [block_id] => platform_info
          [block] => Block Object
              (
                  [content] => View Object
                      (
                          [kohana_filename:protected] => /var/www/galleria.laatikko.biz/modules/gallery/views/admin_block_platform.html.php
                          [kohana_filetype:protected] => .php
                          [kohana_local_data:protected] => Array
                              (
                              )

                      )

                  [css_id] => g-platform
                  [id] => 
                  [title] => SafeString Object
                      (
                          [_raw_string:SafeString_Core:private] => Platform information
                          [_is_safe_html:protected] => 1
                      )

                  [anchor] => 
              )

      )
       )

    * modules/gallery/helpers/gallery_block.php [75]:

      split(  )

    *

      gallery_block_Core::get( platform_info )

    * modules/gallery/helpers/block_manager.php [89]:

      call_user_func( Array
      (
          [0] => gallery_block
          [1] => get
      )
      , platform_info )

    * modules/gallery/controllers/admin_dashboard.php [26]:

      block_manager_Core::get_html( dashboard_sidebar )

    *

      Admin_Dashboard_Controller->index(  )

    * modules/gallery/controllers/admin.php [50]:

      call_user_func_array( Array
      (
          [0] => Admin_Dashboard_Controller Object
              (
                  [theme:Admin_Controller:private] => 
                  [uri] => URI Object
                      (
                      )

                  [input] => Input Object
                      (
                          [use_xss_clean:protected] => 1
                          [magic_quotes_gpc:protected] => 
                          [ip_address] => 
                      )

              )

          [1] => index
      )
       )

    *

      Admin_Controller->__call( index )

    * system/core/Kohana.php [291]:

      ReflectionMethod->invokeArgs( Admin_Controller Object
      (
          [theme:Admin_Controller:private] => 
          [uri] => URI Object
              (
              )

          [input] => Input Object
              (
                  [use_xss_clean:protected] => 1
                  [magic_quotes_gpc:protected] => 
                  [ip_address] => 
              )

      )
      , Array
      (
          [0] => index
          [1] => Array
              (
              )

      )
       )

    *

      Kohana::instance(  )

    * system/core/Event.php [209]:

      call_user_func( Array
      (
          [0] => Kohana
          [1] => instance
      )
       )

    * system/core/Bootstrap.php [55]:

      Event::run( system.execute )

    * index.php [86]:

      require( system/core/Bootstrap.php )