prod and F90 product

Hi,
I'm having strange differences between the R function prod ad the F90 
function product.
Processing the same vector C (see attachment). I get 2 different results:
prod(C) = 1.069678e-307
testProduct(C) = 0

where testProd is the following wrapping function:

testProd <- function(x) {
     return(.Fortran('testProd', as.double(x), as.double(0), 
as.double(0), as.integer(length(x))))
}

subroutine testProd(x, p, q,  n)
     implicit none
     integer, intent (in) :: n
     double precision, intent (in) :: x(n)
     double precision, intent (out) :: p
     double precision, intent (out) :: q
     integer :: i

     p = product(x)
     q=1
     do i = 1, n
         q = q*x(i)
     end do
end subroutine testProd

I check the lowest possible number and seems to be the same for both R 
and F90.
Can anyone help me understanding this behaviour?
Thank you in advance
Regards,
Filippo

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c(0.126667774727727, 0.126778508335206, 0.126889731437094, 0.127001445486345, 
0.127113651944097, 0.127226352279715, 0.127339547970833, 0.127453240503398, 
0.127567431371714, 0.127682122078482, 0.127797314134848, 0.127913009060448, 
0.128029208383447, 0.128145913640589, 0.128263126377241, 0.128380848147438, 
0.128499080513928, 0.128617825048222, 0.128737083330636, 0.128856856950339, 
0.128977147505404, 0.129097956602849, 0.129219285858691, 0.129341136897992, 
0.129463511354905, 0.129586410872726, 0.129709837103945, 0.12983379171029, 
0.129958276362782, 0.130083292741782, 0.130208842537045, 0.130334927447768, 
0.130461549182643, 0.130588709459909, 0.130716410007402, 0.130844652562612, 
0.130973438872731, 0.13110277069471, 0.131232649795309, 0.131363077951156, 
0.131494056948797, 0.131625588584752, 0.131757674665574, 0.131890317007896, 
0.132023517438499, 0.132157277794358, 0.132291599922703, 0.132426485681077, 
0.132561936937394, 0.132697955569994, 0.132834543467704, 0.132971702529897, 
0.133109434666551, 0.133247741798307, 0.133386625856532, 0.13352608878338, 
0.133666132531848, 0.133806759065846, 0.133947970360249, 0.134089768400969, 
0.134232155185011, 0.134375132720541, 0.134518703026945, 0.1346628681349, 
0.13480763008643, 0.134952990934981, 0.135098952745478, 0.135245517594397, 
0.13539268756983, 0.13554046477155, 0.135688851311081, 0.135837849311768, 
0.13598746090884, 0.136137688249485, 0.136288533492915, 0.13643999881044, 
0.136592086385536, 0.136744798413917, 0.136898137103608, 0.137052104675016, 
0.137206703361001, 0.137361935406953, 0.137517803070863, 0.137674308623401, 
0.137831454347986, 0.137989242540865, 0.138147675511187, 0.138306755581082, 
0.138466485085736, 0.13862686637347, 0.13878790180582, 0.138949593757609, 
0.139111944617036, 0.13927495678575, 0.139438632678933, 0.139602974725378, 
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0.839994050316449, 0.844822063204971, 0.849692474666098, 0.854605762797835, 
0.85956241216442, 0.864562913895808, 0.869607765788795, 0.874697472409829, 
0.879832545199546, 0.885013502579025, 0.890240870057837, 0.895515180343878, 
0.900836973455035, 0.906206796832719, 0.911625205457281, 0.917092761965356, 
0.922610036769158, 0.928177608177759, 0.933796062520393, 0.939465994271806, 
0.945188006179693, 0.950962709394249, 0.956790723599879, 0.962672677149092, 
0.968609207198612, 0.974600959847752, 0.98064859027908, 0.986752762901407, 
0.992914151495149, 0.999133439360083, 1.00541131946554, 1.0117484946031, 
1.01814567754173, 1.02460359118558, 1.03112296873426, 1.03770455384584, 
1.04434910080242, 1.05105737467852, 1.05783015151208, 1.06466821847839, 
1.07157237406671, 1.07854342825986, 1.08558220271664, 1.09268953095722, 
1.09986625855153, 1.10711324331065, 1.11443135548128, 1.12182147794325, 
1.12928450641032, 1.13682134963396, 1.14443292961054, 1.15212018179164, 
1.15988405529777, 1.16772551313532, 1.17564553241696, 1.18364510458546, 
1.19172523564088, 1.19988694637132, 1.20813127258717, 1.21645926535893, 
1.22487199125854, 1.23337053260447, 1.24195598771034, 1.25062947113729, 
1.25939211395004, 1.2682450639767, 1.27718948607235, 1.28622656238638, 
1.29535749263372, 1.3045834943698, 1.31390580326946, 1.32332567340966, 
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1.54611202227448, 1.55803659947138, 1.57009336893313, 1.58228412122724, 
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1.8118966257868, 1.82683754899417, 1.84195198668824, 1.85724233669495, 
1.87271103126437, 1.88836053744482, 1.90419335745236, 1.92021202903522, 
1.93641912583231, 1.95281725772524, 1.96940907118308, 1.9861972495989, 
2.00318451361754, 2.02037362145344, 2.03776736919778, 2.0553685911138, 
2.07318015991939, 2.09120498705573, 2.10944602294091, 2.12790625720719, 
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2.30442524081398, 2.32525064591489, 2.34633077080554, 2.36766908628253, 
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2.57192487382806, 2.59604469854048, 2.62046348096394, 2.64518515148636, 
2.67021367508358, 2.69555305041579, 2.72120730883764, 2.74718051331758, 
2.77347675726154, 2.80010016323613, 2.82705488158604, 2.85434508894054, 
2.88197498660324, 2.90994879881949, 2.93827077091539, 2.96694516730204, 
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5.5281594275631, 5.58441843573103, 5.64107035761498, 5.69810378890798, 
5.75550653621385, 5.81326559350816, 5.87136711887098, 5.92979641158084, 
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6.22628196633371, 6.28631830626767, 6.34655366090301, 6.40696571226526, 
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8.98436125304979, 8.99119651415869, 8.99608521283661, 8.99902098391393
)