Calculating lengths of runs of 0 or 1 sequences in meteorological data

Dear List Members,

I need some help about programming in S language. My
problem is as follows:

I have meteorological data (about rainfall measurement
each day from 1989-2002), say like 
http://www.angelfire.com/ab5/get5/data.rainfall.txt 
or http://www.angelfire.com/ab5/get5/R.rainfall.txt
in a sequence of 0(denoting dry day)'s and 1(denoting
wet day)'s. I want to construct a frequency
distribution table of various lengths
(1,2,3,4,5,6,7,8,9,or more) of observed wet spells
(number of successive 1's) and dry spells (number of
successive 0's) occurring in data.

How should i proceed? Is there any existing
program/function/package to solve such problem (seems
like the algorithm should be similar to statistical
run test)?

Any suggestion, direction, references, help, replies
will be highly appreciated.

Thank you for your time.