Update 78 Characters (has order wrong, 2 'push'es to 'unshift's for 6 more characters): (and see note) 
sub f {
while(@_){while(($a=pop)ne'=>'){unshift@b,$a};unshift@{$h{pop()}},@b;@
+b=()}\%h
}

[download]
FSR, '=>' was not being picked up by the qw function in the version of perl here (5.005); I switched to a split on a q function to test the case given: 

my @h = split /\s+/, 
         q[foo => zoo moo too bar => car far bar => zar tar qux => mux
+ ];

print Dumper f(@h);

# output is:
$VAR1 = {
          'foo' => [
                     'zoo',
                     'moo',
                     'too'
                   ],
          'bar' => [
                     'car',
                     'far',
                     'zar',
                     'tar'
                   ],
          'qux' => [
                     'mux'
                   ]
        };

[download]

-----------------------------------------------------
Dr. Michael K. Neylon - mneylon-pm@masemware.com || "You've left the lens cap of your mind on again, Pinky" - The Brain

In reply to Re: (Golf) List to Hash by Masem
in thread (Golf) List to Hash by tadman

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