Maybe you stripped more than what you had to to post your code here, but from what I can see,

my ($buffer,$name,$value,@pairs,$pair);
@pairs = split(/&/, $buffer);
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you are acting on an empty $buffer: the my declaration of $buffer 'initializes' it, so when you use split() to get the values from it, you are acting on an 'empty' variable. You might want to move that

my ($buffer);
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a little higher on your script.

Do you get any warnings that tell you you are acting on undefined data? try printing $buffer before and after the split(), because it might tell you the problem is there...

Update: you say you don't even get 'empty' lines printed, which tells me you never run the for() loop... try to print() @pairs before entering the for()

hope this helps,