ls -l
[email protected]  1 chrisnewland  staff  1664400 14 Sep  2012 swt.jar

To see the extended attributes use the 'xattr' command
xattr swt.jar
com.apple.quarantine
To clear the extended attributes use 'xattr -c'
xattr -c swt.jar
ls -l
[email protected]  1 chrisnewland  staff  1664400 14 Sep  2012 swt.jar