you need -a switch ack -a -f --sort-files /path/to/dir otherwise you only get perl files (-a switch also ignored git/cvs... files/dirs)

Alternatively you can use findrule - command line wrapper to File::Find::Rule

findrule /path/to/dir 
findrule /path/to/dir -file
findrule /path/to/dir -directory
[download]

$ findrule . -directory -name ( Mouse* )
MouseX-AttributeHelpers-0.04
MouseX-AttributeHelpers-0.04/blib/arch/auto/MouseX
MouseX-AttributeHelpers-0.04/blib/lib/auto/MouseX
MouseX-AttributeHelpers-0.04/blib/lib/MouseX
MouseX-AttributeHelpers-0.04/inc/Mouse
MouseX-AttributeHelpers-0.04/lib/MouseX

$ findrule MouseX-AttributeHelpers-0.04 -file -name ( *PL )
MouseX-AttributeHelpers-0.04/Makefile.PL

$ findrule . -file -name ( README ) -maxdepth 2
MooseX-CompileTime-Traits-0.092801/README
MooseX-Getopt-0.23/README
MooseX-Method-Signatures-0.27/README
MouseX-AttributeHelpers-0.04/README
[download]

and just pipe to sort find.... | sort