diff -ruN Module-ScanDeps-1.09/lib/Module/ScanDeps/Cache.pm Module-ScanDeps-1.09-new/lib/Module/ScanDeps/Cache.pm
--- Module-ScanDeps-1.09/lib/Module/ScanDeps/Cache.pm	2012-02-21 07:25:42.000000000 -0800
+++ Module-ScanDeps-1.09-new/lib/Module/ScanDeps/Cache.pm	2012-10-18 04:31:16.312500000 -0700
@@ -57,7 +57,7 @@
 }
 
 ### check for existence of the entry
-### check for identity of the file
+### check for identity of the file, ONLY if mtime is different
 ### pass cached value in $mod_aref
 ### return true in case of a hit
 
@@ -66,6 +66,14 @@
     my ($key, $file, $mod_aref) = @args{qw/key file modules/};
     return 0 unless (exists $cache->{$key});
     my $entry = $cache->{$key};
+    
+    my $mtime = ( stat $file )[9];
+    if (exists $entry->{mtime} and $entry->{mtime}  == $mtime ){
+        ## if mtime hasn't changed, don't bother with md5, its faster
+        @$mod_aref = @{$entry->{modules}};
+        return 1;
+    }
+    
     my $checksum = _file_2_md5($file);
     if ($entry->{checksum} eq $checksum){
         @$mod_aref = @{$entry->{modules}};
@@ -81,6 +89,7 @@
     my $checksum = _file_2_md5($file);
     $entry->{checksum} = $checksum;
     $entry->{modules} = [@$mod_aref];
+    $entry->{mtime} = ( stat $file )[9]; ## cause md5 is slow
     $cache_dirty = 1;
     return 1;
 }
diff -ruN Module-ScanDeps-1.09/lib/Module/ScanDeps.pm Module-ScanDeps-1.09-new/lib/Module/ScanDeps.pm
--- Module-ScanDeps-1.09/lib/Module/ScanDeps.pm	2012-09-04 13:38:32.000000000 -0700
+++ Module-ScanDeps-1.09-new/lib/Module/ScanDeps.pm	2012-10-18 04:33:48.578125000 -0700
@@ -4,7 +4,7 @@
 use warnings;
 use vars qw( $VERSION @EXPORT @EXPORT_OK @ISA $CurrentPackage @IncludeLibs $ScanFileRE );
 
-$VERSION   = '1.09';
+$VERSION   = '1.0901';
 @EXPORT    = qw( scan_deps scan_deps_runtime );
 @EXPORT_OK = qw( scan_line scan_chunk add_deps scan_deps_runtime path_to_inc_name );