It seems to still pass with a couple less ()'s..

 Code:
function a($)
    $ = split($,'/')
    $a = $[0]+'/'+$[1]+'/'+(31-right(_1_1__1_1_3_,$[1])+($[0] mod 4=0 & 2=$[1] & $[0] mod 400=0|$[0] mod 100>))
endfunction


 Code:

KiXtart Version  = 4.62
KiXGolf Script   = kixgolf_eom.kix
Scoring Engine   = 3.3
OS               = Windows XP Home Edition
CPU              = Intel(R) Pentium(R) 4 CPU 2.80GHz
Speed            = 2793 MHz
Memory           = 768 MB

Tournament       = End of Month
Processing Start = 2011/10/24 11:26:04.938
Processing End   = 2011/10/24 11:26:04.954
Duration         = 0000/00/00 00:00:00.015
# Tests Run      = 21
# Tests Passed   = 21
# Tests Failed   = 
Result           = passed
KiXGolf Score    = 132

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