Linker errors for cosyTabs under Lion

gistfile1.txt

Ld /Users/davidf/Library/Developer/Xcode/DerivedData/cosyTabs-dcgcuzxftgpnvkeounisoqrpoewb/Build/Products/Debug/cosyTabs.bundle/Contents/MacOS/cosyTabs normal x86_64
    cd /Users/davidf/Downloads/inket-cosyTabs-95cf70e
    setenv MACOSX_DEPLOYMENT_TARGET 10.7
    /Developer/usr/bin/clang -arch x86_64 -bundle -isysroot /Developer/SDKs/MacOSX10.7.sdk -L/Users/davidf/Library/Developer/Xcode/DerivedData/cosyTabs-dcgcuzxftgpnvkeounisoqrpoewb/Build/Products/Debug -F/Users/davidf/Library/Developer/Xcode/DerivedData/cosyTabs-dcgcuzxftgpnvkeounisoqrpoewb/Build/Products/Debug -filelist /Users/davidf/Library/Developer/Xcode/DerivedData/cosyTabs-dcgcuzxftgpnvkeounisoqrpoewb/Build/Intermediates/cosyTabs.build/Debug/cosyTabs.build/Objects-normal/x86_64/cosyTabs.LinkFileList -mmacosx-version-min=10.7 -fobjc-arc -framework CoreFoundation -o /Users/davidf/Library/Developer/Xcode/DerivedData/cosyTabs-dcgcuzxftgpnvkeounisoqrpoewb/Build/Products/Debug/cosyTabs.bundle/Contents/MacOS/cosyTabs

Undefined symbols for architecture x86_64:
  "_objc_msgSend", referenced from:
      -[NSObject(cosyTabs) new_availableWidthForButtonsWhenUnclipped] in cosyTabs.o
      -[NSObject(cosyTabs) new_tabViewDidChangeNumberOfTabViewItems:] in cosyTabs.o
      +[cosyTabs sharedInstance] in cosyTabs.o
      +[cosyTabs load] in cosyTabs.o
  "_objc_retain", referenced from:
      -[NSObject(cosyTabs) new_tabViewDidChangeNumberOfTabViewItems:] in cosyTabs.o
  "_objc_release", referenced from:
      -[NSObject(cosyTabs) new_tabViewDidChangeNumberOfTabViewItems:] in cosyTabs.o
      +[cosyTabs sharedInstance] in cosyTabs.o
      +[cosyTabs load] in cosyTabs.o
      -[cosyTabs loadPlugin] in cosyTabs.o
  "_objc_retainAutoreleaseReturnValue", referenced from:
      +[cosyTabs sharedInstance] in cosyTabs.o
  "_objc_retainAutoreleasedReturnValue", referenced from:
      +[cosyTabs load] in cosyTabs.o
      -[cosyTabs loadPlugin] in cosyTabs.o
  "_NSLog", referenced from:
      +[cosyTabs load] in cosyTabs.o
  "_NSClassFromString", referenced from:
      -[cosyTabs loadPlugin] in cosyTabs.o
  "_class_getInstanceMethod", referenced from:
      -[cosyTabs loadPlugin] in cosyTabs.o
  "_method_exchangeImplementations", referenced from:
      -[cosyTabs loadPlugin] in cosyTabs.o
  "__objc_empty_cache", referenced from:
      _OBJC_CLASS_$_cosyTabs in cosyTabs.o
      _OBJC_METACLASS_$_cosyTabs in cosyTabs.o
  "__objc_empty_vtable", referenced from:
      _OBJC_CLASS_$_cosyTabs in cosyTabs.o
      _OBJC_METACLASS_$_cosyTabs in cosyTabs.o
  "_objc_msgSend_fixup", referenced from:
      l_objc_msgSend_fixup_alloc in cosyTabs.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)