title: duplicate symbols for architecture armv7
body: <p>Getting following error when try to use Layar SDK in my existing app. How can I solve this?</p>
  
  <pre><code>Ld /Users/pnawale/Library/Developer/Xcode/DerivedData/hub-afxxzaqisdfliwbzxbixsaifljcl/Build/Products/Debug-iphoneos/hub.app/hub normal armv7
      cd /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub
      setenv IPHONEOS_DEPLOYMENT_TARGET 5.0
      setenv PATH "/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin"
      /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch armv7 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS6.1.sdk -L/Users/pnawale/Library/Developer/Xcode/DerivedData/hub-afxxzaqisdfliwbzxbixsaifljcl/Build/Products/Debug-iphoneos -L/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/ZBarSDK -L/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/Infosound/Lib -L/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/CrittercismSDK -L/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub -L/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/UserVoiceSDK-2.0.4 -L/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/Libraries -F/Users/pnawale/Library/Developer/Xcode/DerivedData/hub-afxxzaqisdfliwbzxbixsaifljcl/Build/Products/Debug-iphoneos -F/Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub -filelist /Users/pnawale/Library/Developer/Xcode/DerivedData/hub-afxxzaqisdfliwbzxbixsaifljcl/Build/Intermediates/hub.build/Debug-iphoneos/hub.build/Objects-normal/armv7/hub.LinkFileList -dead_strip -ObjC -all_load -fobjc-arc -fobjc-link-runtime -miphoneos-version-min=5.0 -lMPOAuthMobile -lsbjson-ios -framework LayarSDK -framework Social -framework AddressBook -framework AddressBookUI -framework UIKit -framework QuartzCore -framework Twitter -framework SystemConfiguration -framework Security -framework OpenAL -framework OpenGLES -framework MessageUI -framework MediaPlayer -framework Foundation -framework CoreGraphics -lc++ -framework CoreTelephony -framework CoreVideo -framework CoreMotion -framework CoreMedia -framework CoreLocation -framework CoreData -framework CoreAudio -framework CFNetwork -framework AVFoundation -framework AudioToolbox -lxml2 -liconv -lz -framework MobileCoreServices -lzbar -linfosound -lCrittercism_v3_4_6 -lUserVoice -o /Users/pnawale/Library/Developer/Xcode/DerivedData/hub-afxxzaqisdfliwbzxbixsaifljcl/Build/Products/Debug-iphoneos/hub.app/hub
  
  duplicate symbol _jpeg_free_large in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_free_small in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_get_large in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_get_small in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_mem_available in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_mem_init in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_mem_term in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_open_backing_store in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemname.o)
  duplicate symbol _jpeg_free_large in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_free_small in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_get_large in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_get_small in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_mem_available in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_mem_init in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_mem_term in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _jpeg_open_backing_store in:
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemansi.o)
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jmemnobs.o)
  duplicate symbol _main in:
      /Users/pnawale/Library/Developer/Xcode/DerivedData/hub-afxxzaqisdfliwbzxbixsaifljcl/Build/Intermediates/hub.build/Debug-iphoneos/hub.build/Objects-normal/armv7/main.o
      /Users/pnawale/Documents/Paresh/Yamaha_iPhone/Code/Final/hub/LayarSDK.framework/LayarSDK(jpegtran.o)
  ld: 17 duplicate symbols for architecture armv7
  clang: error: linker command failed with exit code 1 (use -v to see invocation)
  </code></pre>