Solve a second order nonlinear differential equation?

Hi,

I would like to obtain a general solution for x from a second order non linear differntial equation

s* x''[t] + x'[t] - C / x[t] = 0

I used the following code in mathematica as suggested in the mathematica help tutorials:

system = {S*x''[t] + x'[t]- C/ x[t]};
sol = DSolve[{system[[1]] == 0}, {x}, t]

But, I am not able to find any solution with this forumlation of code.. I wonder if this is correct? Any help would be really apprecitaed…

Thank you in advance