Inf in regressions

Hi,

Suppose I I wish to run

lm( y ~ x + z + log(w) )

where w assumes non-negative values. A problem arises when w=0, as log(0) 
= -Inf, and R doesn't accept that (as it "accepts" NA). Is there a way to 
tell R to do with -Inf the same it does with NA, i.e, to ignore it? ( 
Otherwise I have to do something like

w[w==0] <- NA

which doesn't hurt, but might be a bit incovenient sometimes.)

Thanks in advance.

Dimitri