Facing probme with image upload rails 2.3.4, ruby 1.9.2 with papaerclip

I been working on image upload since long and every time working fine,

Now since i deployed application on server,i am facing strange problem
while image upload.

When i am trying upload image it's gives error like,

NameError (undefined method path' for
classActionController::UploadedStringIO'): :10:in synchronize' passenger
(3.0.9)
lib/phusion_passenger/rack/request_handler.rb:96:inprocess_request'
passenger (3.0.9)
lib/phusion_passenger/abstract_request_handler.rb:513:in
accept_and_process_next_request' passenger (3.0.9)
lib/phusion_passenger/abstract_request_handler.rb:274:inmain_loop'
passenger (3.0.9)
lib/phusion_passenger/classic_rails/application_spawner.rb:321:in
start_request_handler' passenger (3.0.9)
lib/phusion_passenger/classic_rails/application_spawner.rb:275:inblock
in handle_spawn_application' passenger (3.0.9)
lib/phusion_passenger/utils.rb:479:in safe_fork' passenger (3.0.9)
lib/phusion_passenger/classic_rails/application_spawner.rb:270:inhandle_spawn_application'
passenger (3.0.9) lib/phusion_passenger/abstract_server.rb:357:in
server_main_loop' passenger (3.0.9)
lib/phusion_passenger/abstract_server.rb:206:instart_synchronously'
passenger (3.0.9) lib/phusion_passenger/abstract_server.rb:180:in start'
passenger (3.0.9)
lib/phusion_passenger/classic_rails/application_spawner.rb:149:instart'
passenger (3.0.9) lib/phusion_passenger/spawn_manager.rb:219:in block (2
levels) in spawn_rails_application' passenger (3.0.9)
lib/phusion_passenger/abstract_server_collection.rb:132:inlookup_or_add'
passenger (3.0.9) lib/phusion_passenger/spawn_manager.rb:214:in block in
spawn_rails_application' passenger (3.0.9)
lib/phusion_passenger/abstract_server_collection.rb:82:inblock in
synchronize' :10:in synchronize' passenger (3.0.9)
lib/phusion_passenger/abstract_server_collection.rb:79:insynchronize'
passenger (3.0.9) lib/phusion_passenger/spawn_manager.rb:213:in
spawn_rails_application' passenger (3.0.9)
lib/phusion_passenger/spawn_manager.rb:132:inspawn_application'
passenger (3.0.9) lib/phusion_passenger/spawn_manager.rb:275:in
handle_spawn_application' passenger (3.0.9)
lib/phusion_passenger/abstract_server.rb:357:inserver_main_loop'
passenger (3.0.9) lib/phusion_passenger/abstract_server.rb:206:in
start_synchronously' passenger (3.0.9)
helper-scripts/passenger-spawn-server:99:in'

(500 Internal Server Error)

but when i am trying second time it working very fine. Any idea ?