diff --git a/GMailinator.xcodeproj/project.pbxproj b/GMailinator.xcodeproj/project.pbxproj
index 47d3494..98126b0 100644
--- a/GMailinator.xcodeproj/project.pbxproj
+++ b/GMailinator.xcodeproj/project.pbxproj
@@ -196,7 +196,7 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "echo \"Grabbing the mail app uuid for your version....\"\necho \"the Source_ROOT ${SOURCE_ROOT}\"\n\ndefaults write ${SOURCE_ROOT}/GMailinator/Info.plist SupportedPluginCompatibilityUUIDs -array-add \"`${SOURCE_ROOT}/find_uuid.sh`\"";
+			shellScript = "full_version=$(sw_vers -productVersion)\nmajor_version=$(echo $full_version | awk -F \\. {'print $1'})\nminor_version=$(echo $full_version | awk -F \\. {'print $2'})\n\necho \"OSX v${major_version}.${minor_version}\"\n\nif [ \"$major_version\" -ge \"10\" -a \"$minor_version\" -ge \"12\" ]; then\n    compatibility_key=Supported${major_version}.${minor_version}PluginCompatibilityUUIDs\nelse\n    compatibility_key=SupportedPluginCompatibilityUUIDs\nfi\n\nmail_uuid=$(${SOURCE_ROOT}/find_uuid.sh)\n\necho \"UUID for your version of Mail.app: ${mail_uuid}\"\n\nif defaults read ${SOURCE_ROOT}/GMailinator/Info.plist ${compatibility_key} | grep \"${mail_uuid}\" >/dev/null; then\n    echo \"UUID already exists in ${compatibility_key}\"\nelse\n    echo \"Adding UUID to ${compatibility_key}\"\n    defaults write ${SOURCE_ROOT}/GMailinator/Info.plist ${compatibility_key} -array-add \"${mail_uuid}\"\nfi";
 		};
 /* End PBXShellScriptBuildPhase section */
 
diff --git a/GMailinator/Info.plist b/GMailinator/Info.plist
index c01268f..2b90c37 100644
Binary files a/GMailinator/Info.plist and b/GMailinator/Info.plist differ