macos - ls -la symbolics... what does that last symbol mean?

Possible Duplicate:
what does the @ mean on the output of ls on os x terminal?

when I type ls -la I get this familiar output...

drwxr-xr-x+  38 kent  staff       1292 Nov  6 11:09 .
drwxr-xr-x    5 root  admin        170 Aug 14 14:11 ..
-rw-r--r--@   1 kent  staff         16 Jun 18 14:13 .AB64CF89
-rw-------    1 kent  staff          3 May  5  2009 .CFUserTextEncoding
-rw-r--r--@   1 kent  staff      15364 Nov  6 11:11 .DS_Store

my question is about the file settings on the far left eg:

drwxr-xr-x+

I know that the first char 'd' means directory. and the next 9 chars I understand as well (permissions) but what is the final char in this field? (empty or + or @ )