they are two completely different things, and as such, cannot be directly compared.
as you likely know, candlepower is a measurement of light at a given point.
lumens is a measure of overall light.
as such, you can have a laser, which has extremely high candle power and extremely few lumens.
or you can have a ledlight, or a surefire-type light that has much fewer candlepower, but more lumens.
of course, for lighting use, you'd wouldn't pick the laser /ubbthreads/images/graemlins/grin.gif
that's a crude example, and comparing a laser to a normal flashlight isn't exactly fair, but you get the idea of the measurements.
lights that have long throw tend to be measured with candlepower, because it makes them look brighter (and it's just a good way to tell how far they throw..), whereas lights not intended for extra-long throw tend to be measured in lumens.
of course, how lights are rated varies, but cp and lumens are two measurements to describe different two different things (i think i said that above /ubbthreads/images/graemlins/grin.gif )