Update to byobu in stable to fix bug #548717

[Alexander Chernyakhovsky <achernya@MIT.EDU>]

Hi All,

I encountered bug #548717 on my Debian Squeeze system that uses kerberos 
authentication and hesiod groups. Unlike the situation described in the 
bug, I could not easily remedy this by deleting the directory -- the 
package was not installable.

I have corrected this by backporting better chmod semantics, which makes 
this package installable, and tested it.

Thanks.

Sincerely,
-Alex Chernyakhovsky