nntool problem

I was trying to train the nntool with a feature vector of the no.of black pixels in a box in an image divided into 5*5 boxes where there is 5000 images for the digits from 0 to 9 .

so the input matrix for training is 25*50000

the target matrix dimensions is (as I think )10*50000

with a pattern of the following form:

target=zeros(25,50000);
target(1,1:5000)=ones(1,5000);%this correspond to zero
target(2,5001:10000)=ones(1,5000);%this corresponds to one

and so on

so my questions are:

are the dimensions of the target matrix correct?

and if so (if correct) i got an error message:

??? Insufficient number of outputs from right hand side of equal sign to satisfy assignment.

Error in ==> nntool at 681
      [errmsg,errid] = me.message;
which I know from previous question on this forum that it is an out of memory error.

 I'm having Matlab r2009 a,4GB RAM and 2.00 GHZ Intel core 2Duo .
so please what should i do?