another codesign attempt

Rakefile

@@ -81,8 +81,8 @@ namespace :build  do
         sh "cmake -DIOS=1 -DCMAKE_BUILD_TYPE=Release -G Xcode ../../"
         sh "KEYCHAIN=/Users/jenkins/Library/Keychains/codesign.keychain"
         # the -s option adds $KEYCHAIN to the search scope, while the -d option adds $KEYCHAIN to the system domain; both are needed
-        sh "security -v list-keychains -d jenkins -s $KEYCHAIN"
-        sh "security -v unlock-keychain -p codesign $KEYCHAIN"
+        sh "security -v list-keychains -d system -s $KEYCHAIN"
+        sh "security -v unlock-keychain $KEYCHAIN"
         sh "xcodebuild -configuration Release"
       end